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Biology 103 Fall 2005 Papers Forum

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Milk is Milk?
Name: Keti Shea
Date: 2005-11-13 16:07:02
Link to this Comment: 16950


Biology 103

2005 Second Paper

On Serendip

Since the Food and Drug Administration approved recombinant bovine growth
hormone(BGH or rBST)for commercial use in 1993, about 1/3 of all U.S. dairy farmers have begun use of rBGH in order to increase milk production (2). This translates to as much as 15% more milk produced than in non-rBGH cows, or 5-15 more pounds of milk per cow per day (5). While bovine somototropin (BST) occurs naturally in all cows as a protein which stimulates the production of milk, synthetic BST is produced through recombinant DNA technology (7). In this process, cow genes with somototropin-producing cells are isolated and inserted into a bacterial cell (7). When this bacteria cell then multiplies, it produces rBGH (7). While commercial dairies and proponents of agribusiness support rBGH as a safe and effective way to increase milk production, other voices such as consumers' groups and environmentalists have reacted against the use of recombinant bovine growth hormones as posing serious health risks to both animals
and humans.

One such concern is the claimed link between the consumption of rBGH milk and breast and colon cancers. For example, the Cancer Prevention Coalition argues that use of rBGH increases level of insulin-like growth factor or IGF-1, already present naturally in cows and humans (4). While human and natural bovine IGF-1 are bound to protein, synthetic IGF-1 is unbound, making it more biologically active (5). This is a significant finding given that IGF-1 is not destroyed by pasteurization or digestion and can be absorbed across the intestinal wall (1) . The link to cancer becomes more apparent after considering the function of IGF-1: to induce the division and multiplication of normal human breast epithelial cells (4). In addition, it has been suggested that IGF-1 maintains the malignancy of breast cancer cells and inhibits apoptosis, the process by which unwanted cells essentially commit suicide (programmed cell destruction) . In this way, increased
levels of IGF-1 inhibit the possible elimination of cancerous cells

Besides the effects on humans, IGF-1 is also said to affect rBGH cows, leading to an increased occurrence of pathological lesions, infertility and chronic mastitis (2). Mastitis, or udder infection, is of particular importance because it presents the possibility that pus from infected cows will contaminate milk (6). Additionally, increased occurrence of infections necessitates the increased usage of antibiotics,leading in turn to possible antibiotic resistance or allergic reactions (5).

The dairy industry however stands firm in its rejection of the notion that rBGH milk differs in any way from non-rBGH milk. This argumentation has been led by Monsanto, the $4.7 billion multinational corporation which is the sole commercial producer of rBGH in the United States. Data from Monsanto released to the FDA (but not to the public) revealed up to an 80% increase in the occurrence of mastitis and "resulting contamination of milk with statistically significant levels of pus; this will necessitate virtually routine use of antibiotics, with attendant risks of allergic reactions and antibiotic resistance" (4). Despite these claims and the
company's own data, Monsanto together with the International Dairy Foods Association(IDFA), contend that rBGH poses no health risks. Rather, they argue, bovine growth hormones occur naturally in cows; the public should not change their milk consumption based on a poor knowledge of biotechnology or on misleading claims made by organic milk companies (9). Monsanto states that there is no difference in cows treated with rBGH or in their milk nor has there been an increase in the occurrence of mastitis (7). This comes despite the statement made by Samuel Epstein of the Cancer Prevention Coalition that saturated fatty acids linked to heart disease increased in rBGH milk while thyroid hormone enzymes decreased (5). Monsanto representatives argue, however, that even when mastitis does occur, the infected cows are removed from the milk production process and safely treated (7). Furthermore, they conclude that rBST does not affect humans as it is biologically inactive once it enters the human body (8).

Finally, we see that this debate centers around claims of who is a better scientist. On the one hand, consumer and environmentalist groups attack Monsanto as an example of the perniciousness of multinational corporations which have turned the milk industry into agribusiness, potentially harming millions in order to increase their own profits. Monsanto, on the other hand, claims that biotechnology can be a powerful tool, if people will only accept it. In fact, Monsanto's official statements mention the potential use of biotechnology in alleviating world hunger: " 'We're taking calculated, appropriate steps. It's science-driven. It's the drive to feed more people, to solve finite food issues' " (7). In fact, while Monsanto currently sells products which increase yield or productivity, it is working on genetically-
engineered plants which would be more nutritious for consumers. Yet it is consumer groups, such as the Consumers Union, which attack Monsanto as overlooking consumers in their own greed for more profit. The House Committee on Government Operations stated " 'that Monsanto and the FDA have chosen to suppress and manipulate animal health test data–in efforts to approve commercial use' " (5). This report is similar to one published previously concluding that the " 'FDA has consistently disregarded its responsibility–has repeatedly put what it perceives are interests of veterinarians and the livestock industry ahead of its legal obligation to protect consumers..' " (5). While Monsanto continues to argue that its facilities use good science to produce sound products, 9 million cows are being
injected with rBGH in the United States, leaving consumers to answer the question: is Milk really Milk? In short, is genetic engineering the key to the future, to the alleviation of world hunger or is it just an example of bad science?

WWW Sources
"Monsanto's Hormonal Milk Poses Serous Risks of Breast Cancer, Besides Other Cancers
from Cancer Prevention Coalition website.

, from the National Post.

, from the St.Louis Post-Dispatch.

4)"A Needless New Risk of Breast Cancer", from the Los Angeles Times.

5)"The 'Milk is
Milk' Industry Campaign Threatens Public Health"
, from Ascribe Newswire.

6)"Genetic Engineering Stuck in the Dark Ages of Science", from Greenpeace

"Monsanto's Vision of Biotech"
, from Portland Press Herald.

, from Monsanto website.

9) "Biotechnology
and BST"
, from International Dairy Foods Association website.

A Cure Which Offers Even More Grief? : The Use of
Name: Lizzy de V
Date: 2005-11-13 17:27:04
Link to this Comment: 16954

<mytitle> Biology 103
2005 Second Paper
On Serendip

To her classmates, teachers, and friends, Allison* was a thirteen-year-old who everyone admired and wanted to be like. Unlike most young adolescents, she seemed to effortlessly balance an active social-life, honors level academics and demanding extra-curricular activities. She was an accomplished violinist and had a strong relationship with her family. Mid-way through the eighth grade, Allison's personality began to change drastically. Her grades dropped and her interests in socializing and in music declined. Many evenings her parents found her lying in bed staring at a wall. She answered questions with only one word, and later admitted that it just felt like it took too much effort to speak in full sentences. Three months before her fourteenth birthday, Allison made a feeble attempt at committing suicide. The next day she was diagnosed with Major Depression and put on a high dosage of anti-depressants.

Over the course of the following month, Allison began to feel happier than she ever had in her life. Her confidence was so high that it seemed absurd to others, and sometimes to herself. She now confesses that she felt so powerful that she once crossed a busy two way street in traffic, never looking either way. Her mind told her that there was no way a car could possibly hit her. Allison loved the extreme euphoria she was experiencing, but it was clear to her parents and doctors that her emotions were not normal. She was re-diagnosed with Bipolar I Disorder.

Bipolar I Disorder is a complex and severe mental illness. Patients suffer from periodic episodes of depression and mania, typified by inflated self-esteem, hyperactivity and reckless or impulsive behavior. If Bipolar I is not treated, it has an approximately 15% risk of death by suicide. Shockingly, the disorder is the third leading cause of death among people aged 15-24, and the sixth leading cause of disability for people aged 15-44 years. It is a lifelong disease with both genetic and environmental factors of causation. Some illnesses such as multiple sclerosis and hyperthyroidism can cause mania. As in the case of Allison, antidepressant medication can also trigger mania. Manic episodes usually last for between two weeks and five months, while depression can last up to a year or more. (4)

When Allison was diagnosed with Bipolar I Disorder, her psychologist put her on Eskalith, a form of Lithium, the medication prescribed most often to treat Bipolar Disorder. It evens out mood swings and usually reduces manic symptoms in one or two weeks. (3) Lithium, an alkali salt, was discovered in 1817, and in the late 1800's doctors using it to treat gout began to hypothesize that it might have mood stabilizing properties as well. In 1949, Australian psychiatrist John Cade published the first paper on the use of lithium as a remedy for acute mania, and the U.S. Food and Drug Administration approved lithium for us in 1970. It was not until 1998, however, that scientists began to have any idea of how or why it worked. Researchers at the University of Wisconsin found that lithium acts on receptors for the neurotransmitter glutamate. Too much glutamate in the space between neurons causes mania, and too little causes depression. Lithium keeps the glutamate level at a stable level. (8) Another hypothesis proposes that lithium alters membrane excitability by partially replacing sodium, and yet another theory says that it manages calcium levels, which have been found to be low in depressed individuals and high in people experiencing mania. (1)

While lithium has been established as the primary pharmaceutical treatment for Bipolar I Disorder, in many cases it has been found to cause as much harm as it does good. Initially, patients taking lithium can experience side effects such as drowsiness, weakness, nausea, fatigue, increased thirst and urination, and hand tremor. (3) Allison was particularly distressed by the tremor. She was embarrassed that it was difficult for her to bring a soup spoon to her mouth, and holding her violin and bow became increasingly difficult. Researchers have found a wide range of occurrence of lithium tremor, 4% to 65%. (2) On an message board for individuals with Bipolar I, some complained of excessive hair loss and even memory loss. "I have lost memory for periods of time of an hour or more completely. I have no recollection of conversations I was involved in during these times, or even places I've been to during these times. I have even zoned out so badly that I have 'woken up' out of my daze, sitting in a parking lot somewhere, not knowing how I got there or how long I had been there. It's truly frightening..." (9)

Lithium has also been proven to cause weight gain. This may be due to lithium-induced hypothyroidism, which slows down the metabolism, or increased thirst which leads people to drink high-calorie fluids. In a 1999 study, researchers found that a molecular receptor known as 5-HT1B is a "target" for lithium. 5-HT1B are controllers of the system that distributes serotonin, a neurotransmitter affecting depression and appetite. One post on stated "Gained 75 lbs. since I began lithium. I have always been petite now 200+. I am 5'3" and was a marathon and long-distance runner. You ask, "why doesn't she just go out and run?"...duh, lithium is sedating. In me it causes a "nothing really matters any more, I'll just sit in my chair for a week and veg-out" attitude. Gaining weight has caused me to feel humiliated, painful physically, caused isolation because of shame." (9)

Allison experienced an atypical side-effect of lithium. In her senior year of high-school, after four years taking a combination of lithium and anti-depressants, she began to experience shortness of breath and a racing heart beat. She had a consistent blood pressure of at least 140 over 100, extremely high for a young girl in good physical health and condition. After many tests, it was determined that Allison was experiencing hypertension, however, it could not be determined why. She increased her exercise and went on a very low-sodium diet, but it wasn't until she was taken off lithium and put on another mood-stabilizer, Depakote, that her blood pressure returned to a perfectly normal 120 over 80. There is no scientific proof that lithium can cause high-blood pressure, and psychiatrists say that what Allison went through was extremely rare. But as is the case for many Bipolar I patients, being on lithium made Allison's quality of life even worse than it already had been for a young girl dealing with a difficult disorder.

For children and adults, Bipolar I is an extremely confusing and grueling disorder. Patients and their families and friends alike find it very difficult to understand why individuals with Bipolar I are the way they are, and relationships are often negatively affected. It seems to me that it is a horrific reality that the primary treatment for this disorder can cause patients so much grief. Hopefully, the psychiatric and scientific community will continue to endeavor to discover more beneficial medications so that those who already suffer mentally do not have to endure physical issues as well. I was pleased to read that Tamoxifen, an anti-estrogen drug used as a preventative measure for women at high-risk for breast cancer, is currently being studied as a possible treatment for mania. Tamoxifen is an inhibitor for protein kinase C, a signaling pathway within nerve cells which has been found to have some involvement in Bipolar Disorder. (10) I am optimistic that one day, doctors will be able to offer patients true freedom from the hardships which I suppose only those who have experienced mania and depression can truly comprehend.

*Allison is a real person who I am well-acquainted with. Her name has been changed.

WWW Sources
1)Biological Theories of Manic-Depression, on the Serendip website
2) Gelenberg, A.J. "Lithium Tremor." J Clinical Psychiatry, Vol. 56 (1995), pp 283-7
3)Medications for Bipolar Disorder , on the website
4)Bipolar I Disorder, on the Internet Mental Health website
5)The Antisuicidal Effects of Lithium, on the McLean Hospital Psychiatric Update website
6)Lithium, on the MHRA website
7)Medications, on the National Institute of Mental Health website
8)Lithium: The First Mood Stabilizer, on the website
9)Speaking From Experience: Lithium, on the website
10)Tamoxifen – Serendipity for Bipolar Disorder?, on the website

Health benefits and risks of veganism
Name: Stephanie
Date: 2005-11-13 17:37:31
Link to this Comment: 16955

<mytitle> Biology 103
2005 Second Paper
On Serendip

As Americans, we probably take our food for granted and rarely spend time thinking about its production. When we eat a hamburger we probably don't think about the energy put into growing food for the cow, raising the cow and we certainly avoid thinking about the slaughter of the cow. The U.S. Department of Commerce and Interior stated that a third of all raw materials consumed are in the production of animal based foods (1). Now, I know this sounds a lot what your parents used to say when you didn't eat your lima beans at dinner, but there are people all over the world who would kill for the food we have. By eating vegan, which is to cut out all animal products from one's diet, we can indirectly minimize our consumption. I would like to point out before delving into the controversy surrounding the topic of vegan diets that I am not vegan or vegetarian, but I do make a conscious effort to eat as little meat and dairy as possible. Although there are many reasons that a person might become vegan, such as environmental reasons or simply a concern for animals, many people become vegan because of the health benefits. The more I explore this topic, the more controversy I have found, particularly in the area of raising vegan children. As I was researching, I kept the mindset that what I was should be either trying to persuade me to become vegan or not to become vegan, so I will outline the arguments that I found to be most persuasive.

Surprisingly, (or maybe not surprisingly), most sources about vegan health focused on what needs to be done in order to make a vegan diet healthy instead of why a vegan diet can be intrinsically healthy. This suggests to the skeptic of veganism that a vegan diet in and of itself is not healthy as it needs to be supplemented with numerous other vitamins and minerals and meals need to be planned in such a careful way. There are however, some benefits to eating no meat and lots of veggies. Heart disease is strongly correlated with high cholesterol, which is found for the most part in meat products (1) and eggs (5). Eating vegetarian can reduce a person's risk of heart disease by 30% (4). This may be helpful for a person with high cholesterol who is at risk for heart disease. Also, it has been found that even just reducing 5% of the saturated fats from dairy products and replacing them with unsaturated fats lowers the risk of heart attack and death from heart disease by 40% in women (3). Although the study mentions nothing of its generalizability to men, I would be hesitant to make such a generalization, based on the idea that men and women store fat differently. Eating vegetarian is also claimed to have the following benefits: reduce your risk of "certain cancers" (source is unclear as to what cancers in particular) by 40%, kidney and gallstones, diet-related diabetes, high blood pressure and health problems related to obesity (4). The consumption of animal fats has been linked to numerous health problems: heart disease, colon and lung cancer, osteoporosis, diabetes, kidney disease, hypertension and obesity (among others) (5). This again is correlational data and does not imply that animal fats cause these conditions, but it may be helpful for people who are prone to developing one or more of these conditions to change their diet to include fewer animal fats. Antibiotics, hormones and other toxins are used in the production of meat products. In many cases, these accumulate in the animal fat and people then consume them. Futhermore, excessive protein intake can lead to colon cancer and osteoporosis (1).

Thus far, the health benefits of "veganism" seem to be consistent with those of vegetarianism. There seems to be nothing in particular about veganism that makes it healthier than simply cutting out or even reducing meat products. Vegan foods tend to be low in fat and high in fiber and nutrients (5). This could be particularly beneficial to people on specialized diets. There are some vitamins and minerals that come from particular plants. Iodine is best received from plant products; selenium comes from Brazil nuts; D2 from shitake mushrooms, Omega-3 fatty acids from flaxseed oil (2). These are foods that a vegan may be more likely to eat than a non-vegan, but still gives no argument for eating a solely vegan diet. Also, it seems as though many of the benefits come from eating organic foods: whole grains, strongly colored vegetables, avoidance of over-processed foods containing hydrogenating vegetable oils (2).

Vegans must make sure to get all of their daily dosages of vitamins and minerals. This requires supplementation. The most common supplement among vegans is vitamin B-12 as well as other B-vitamins (1). B-12 is important because it regulates the levels of homocysteine in the blood. Without B-12, a person can suffer from sever irreversible brain damage and with a slighter deficiency of the vitamin, one can suffer from unusual fatigue, faulty digestion, nausea, loss of appetite and amenorrhea (6). B-12 can be found in vegan foods such as nutritional yeast, inactive yeast and in foods like soy-milk which can come fortified with B-12 (6). The health benefits of eating vegan can be achieved just as easily by eating a vegetarian diet, and all the necessary nutrients can be included in a vegetarian diet without supplementation, although vegetarians must also monitor their intake of B-vitamins to be sure that they are consuming enough (1).

In addition to B-vitamins, vegans may also lack iron, protein, zinc and calcium, of which meat and dairy products are the typical sources. However, it is possible to get iron and zinc from whole grains, nuts, seeds and legumes. Protein is found in low levels in most plant foods: lower levels in fruits and higher levels in legumes. Calcium is found in spring greens, kale, mustard greens or Chinese cabbage and calcium-enriched soy milk can easily be purchased at an organic market (2). Calcium can also be better retained in the body by adding a tablespoon of salt to your diet daily or by adding potassium (3). These vitamin and mineral sources demonstrate the careful planning aspect of veganism. It is important to know what vitamins and minerals come from what foods and to plan meals accordingly without eating a monotonous, non-varied diet. For most people, this is a difficult and impractical task and if they eat only vegan foods, their health could suffer as a result.

As I mentioned previously, the most debate in the health aspect of veganism is whether or not it is healthy for children. Anecdotally, there have been claims made that mothers can have healthy children even if they are vegan during pregnancy and while breastfeeding. Pregnant women who eat a varied vegan diet with a reliable source of B-12 will have a healthy baby (7). Also, claims have been made that infants and children can be healthy following a vegan diet (1). Cow's milk may contain too much fat and protein for infants, as it is intended naturally for baby calves (5), meaning breastmilk is the healthier option for young babies. A benefit of a breastfeeding vegan mother is that her breastmilk will not have the toxins and pesticides that a meat-eating mother's breastmilk will have (7). However, there is contradictory evidence showing that vegan mothers suffer from a vitamin deficiency and their breastfeeding children are likely to suffer from disorders such as vitamin B-12 deficient anemia, dystrophy, weakness, muscular atrophy, loss of tendon reflexes, psychomotor regression, and haematological abnormalities (1).

It is possible for children to safely follow a vegan diet, as long as proper supplements are available. Some people even claim that children who are vegan are healthier because they eat more fruits and vegetables. They get sick less often and have fewer food allergies (7). Infants who have passed the breastfeeding stage tend to eat primarily vegan anyway: mashed fruits and vegetables (7). On the other hand, a vegan child may have low volumetric stomach capacity and it has been found that vegan parents tend to limit the number of meals and snacks, as well as the caloric intake of their children (1). Recently, a couple was charged with neglect of their four children because the enforced a strict raw foods diet. This was a case taken to the extreme, as the refrigerator was locked and the children were taught that cooked foods are "evil" (8). The case does show, however, that vegan parents need to be careful to make sure that their children are receiving proper nutrition while they are developing.

There was little compelling evidence that eating vegan is a particularly healthy diet and can be, in fact, very dangerous for those who do not know exactly what they are doing. Meals must be well planned to include all the proper nutritional elements. There are however, some health benefits to avoiding meat products and eating more vegetables, but one does not necessarily have to be vegan to do so. It seems to me that diet is a very individualized topic: some people may be healthier when eating less meat some people may be healthier eating no meat and some people may be healthier eating fewer vegetables. A diet will probably work best when individual differences such as how active a person is and what diseases they may be predisposed to are taken into account, but one thing is certain for all diets: they need to be balanced to ensure proper nutrition. I guess there actually was some importance to the ever-changing food pyramid that every child learned in fifth grade health class.

WWW Sources
1)The Good, The Bad and The Vegan
2)The Vegan Society: Nutrition
3)The Vegan Society: Dairy products and health
4)The Food Doctor
5)Vegan Action: About veganism
6)Mid-Hudson Vegetarian Society. B-12: The misunderstood vitamin
7)VegFamily: Raising children vegan.
8)Vegan couple cleared of starving child, guilty of child neglect.

Lactose Intolerance
Name: Magdalena
Date: 2005-11-13 18:15:29
Link to this Comment: 16956

<mytitle> Biology 103
2005 Second Paper
On Serendip

Lactose Intolerance


Magdalena Michalak


            Embarking on this web paper has been an almost wholly selfish endeavour on my part, and one which I'm rather surprised I hadn't already ventured into on a more informal basis earlier on.  However, I'm quite pleased to know that my findings will be published online, as non-scientific as they are, because more lactose intolerant people could benefit from understanding precisely why they can't tolerate milk products and what they can do about this.

            The key question for this paper developed when I was roughly seventeen years old and first realized that I was having problems with milk products.  I was used to drinking three or four glasses of full milk every day as I had since I was a child (my father was born in a village, and both eggs and milk were staple daily food items, obtained fresh from the back yard or the neighbour's dairy), and here I was noticing that after drinking milk it'd "sit" in my stomach for a while.  Enough of this and I finally just gave up my milk-drinking habits and turned more to other sources of dairy products, but even cheese bothered me after a while.  It really took me some time to put two and two together as to lactose intolerance since at this time, as throughout my life, I was traveling constantly and these milk issues weren't consistent—it took me even longer to notice that I only had milk-related digestive issues in the US.  Why was I only having issues in the US?  What was different about milk "there"—the rest of the world—from milk here?

            I have always been skeptical of the modern American farming institution.  At this point, it really isn't about farms and farmers; it's business, pure and simple, and as in any large-scale corporation, quality is lost in the search for quantity.  It doesn't surprise me, then, that the milk situation in the states is at the same state as that of tomatoes: large quantities of visually appealing, pesticide-laden product that resembles its predecessor not one bit, can last for weeks on shelves, and is sterile of both taste and nutritional value.  In the case of milk, the product not only loses almost all of its nutritional value, it also makes it impossible for a good portion of individuals to digest in the first place.

            Pasteurization (1) was a process invented in France in 1862 as an alternative to sterilization.  In 1886, it was applied to milk, and by the 1920s or thereabouts became the standard treatment for raw milk in the US.  Around this time, illnesses contractible through contaminated milk (most notably tuberculosis) were widespread and, instead of tackling the root of the problem—namely, increasing sanitation standards and enforcing them more harshly—it was decided that pasteurization would be instated.  This way even "dirty" (2) milk that had been contaminated along the way could be purified enough for human consumption.  Presto, the beginning of an industry which focused on the end product rather than the steps required to make it.  Grass-fed cows kept in small herds were replaced by huge herds kept in cement bunkers and fed processed feed products pumped full of antibiotics (not to mention other cows, which led to the rise of bovine spongiform encephalopathy).  While there were other factors involved in this mass-commodification of the small dairy farm, the end results have been the same.  Today's store-bought milk is stripped of natural nutrients, full of chemicals, and difficult to digest.

            What does this have to do with lactose intolerance?  It's precisely that stripping of nutrients which causes almost all lactose intolerance (as opposed to a true lactose allergy, which is a subject for another paper) since this intolerance is caused by a lack of the enzyme lactase in large enough quantities within the human digestive system to break down lactose, a fairly complex disaccharide found in milk.  Raw milk contains harmless bacteria which produce lactase which, in turn, enables the human body to break down and absorb lactose.  Pasteurized milk has had all of these bacteria killed off and is therefore lactase-free, but still contains lactose, causing problems for many people who try to drink it.

            Why should this be a concern in the US in particular?  Clearly other countries pasteurize milk, as well, but the type of pasteurization (4) process used varies widely from country to country, with both temperatures and exposure times subject to individual government regulations.  In the majority of the world, raw milk products are not illegal (in the US, selling domestic raw milk products is legal in 28 central states but not widespread by any means because of store regulations which essentially make it impossible) and the pasteurization process permits many more microorganisms to remain in the milk.  A good test for this, for example, is the sour milk test.  Milk which has had beneficial bacteria killed off will, if left out in the open, spoil/decompose; bacteria flourish and the milk takes on a putrid odour.  Milk which has only been gently pasteurized will instead sour; its consistency will thicken as bacteria produce more acids, and yeasts in the milk will turn it into first sour milk (a beverage which sounds unpalatable to Americans but is delicious, healthy, refreshing, and a wonderful digestive aide to a heavy meal), then sour cream.  Most countries aside from the US, England, and Italy do not pasteurize their milk to the point of killing off these beneficial microorganisms.

            The sources I cite below can offer more thorough, academic findings which demonstrate how little nutritional value is left in pasteurized milk and how healthy low-pasteurized or unpasteurized milk products really are.  There are studies (3) dating well back into the 1930s which show how much healthier children raised on raw milk products were, and studies tying pasteurized milk products to decreased bone density, weakened tooth enamel, vision problems (from vitamin B6 insufficiency), and a large increase in asthma.  It's not surprising, then, that these problems are mostly American problems—there has been no sharp rise in asthma in most parts of the world, and most parts of the world have worse pollution problems than the US.  The Diagnose-Me site even gives percentages based on ethnic origin of populations in the US of people with lactose intolerance.  I would really like to know how this would correlate to the ethnic distribution in the US; my guess would be that in the Midwest, where there are more dairy farms and easier access to raw milk products and where the population is almost wholly white, there are much fewer occurrences of lactose intolerance, therefore tipping the Caucasian percentages.

            Thanks to the media highlighting the dangers of bacteria, yeast spores, and viruses, the US public is paranoid of anything that might be "dirty" or not sterilized past the point of recognition.  Raw products of any sort are highly controlled by the government, but one has to wonder why.  As one source (5) states, people were around and alive long before pasteurization.  There is also as startling lack of awareness of this issue in the media; rather than producing drugs which artificially introduce lactase back into the human body, shouldn't we be focusing on tackling the root of the problem—overpasteurized milk?  If more people took matters into their own hands and sought out raw milk products, as well as contacting their local representatives about easing the legislation for these products, the health benefits for the entire nation could be phenomenal.









The raw milk movement:



The Avian Flu: Coming to a City Near You?
Name: Kate Drisc
Date: 2005-11-13 21:58:02
Link to this Comment: 16961

<mytitle> Biology 103
2005 Second Paper
On Serendip

The avian flu, while typically hosted by birds, has been infamously known to transmit to human beings, producing catastrophic results. The avian flu is currently a serious issue of concern, as its effects are being felt worldwide. It was first identified in the early 1900's in Italy and has remained a potent threat, as the death toll from this virus continues to rise. Historically, the most destructive avian flu was the 1918 "Spanish flu", which is thought to have killed 50 million people. Currently, the H5N1 strain of the avian flu, a highly pathogenic form of the virus, has spread throughout many parts of Asia and into Europe, killing many people and birds. Fear of another avian flu pandemic is mounting, as scientists work diligently to develop innovative treatments and governments try to sequester the fears of civilians. Due to the attention that this disease has been receiving as well as the emphasis that has been placed on the need to self-protect, both the nature of the disease as well as available treatments are worthy of further exploration. (1)

The avian flu virus is composed of the Influenzavirus A genus of the Orthomyxoviridae family and is a single-stranded, segmented RNA virus. Flu viruses are subdivided into subtypes according to antigens in the haemagglutinin (H) and neuraminidase (N) protein projections on their surfaces. The avian flu has representatives in all of these subtypes, but the most common avian viruses belong to either H5 or H7 subtypes. Furthermore, the avian flu virus can be subdivided into either high or low pathotypes depending on its virulence. (2)

At this point one might be asking the fairly obvious question: if this is a bird flu, how can people contract the virus? It is indeed true that the avian flu originates in waterfowl, birds, and domestic poultry, but the flu can be easily transmitted through their saliva, feces and nasal secretions to humans. While a weaker strain of the virus infects the respiratory and gastrointestinal tracts of birds, a highly pathogenic strain such as the H5N1 strain that is currently plaguing Asia and Europe, can spread to virtually all parts of an infected bird or mammal, including the meat. Therefore, H5N1 can be spread through the distribution of contaminated food products. This strain of the virus is also able to survive in low temperatures and therefore can be found in frozen meat. H5N1 can also last for up to 35 days at low temperatures in the feces of these infected animals and can survive on surfaces, such as those within the poultry house environment, for several weeks. (3)

Human outbreaks of strands of the avian flu have originated in crowded conditions where poultry and humans live in close quarters, as demonstrated with the current outbreak of H5N1 in eastern Asia. Another point to note is that many birds are migratory, and are therefore able to spread the virus to all parts of the world. Viruses also replicate and mutate at such a high rate that they are able to evolve into a form that more easily infects humans. Furthermore, the virus could mutate to the point that it can be easily spread during human-to-human contact, which was the case in the 1918 avian flu pandemic. Coughing, shaking hands, and traveling in airplanes could potentially provide the optimum environment for procreation of this virus. Therefore, due to the ability of the virus to rapidly mutate, spread, and kill, it is clear why this issue is receiving so much global attention. (2)

The H5N1 strain of the avian flu has been circulating in Asia since 1997. In 2004 and 2005, 118 people were infected with the H5N1 virus and 61 of them died. More than 120 million birds have died as a result of this strain of the avian flu, or have been killed to prevent further infection. This particular strain (H5N1) goes directly deep into the lungs, causing severe pneumonia, and in many cases, death. This is unlike the normal human flu, which predominantly affects the upper respiratory tract causing congestion, runny nose, and sore throat. (2)

Although H5N1 does raise serious health concerns, there are defenses available to combat this virus. First and foremost, prevention tactics adopted by many governments focus on killing infected animals as well as those suspected of being infected. While killing infected animals will certainly limit the spread of disease, it seems virtually impossible to effectively stop it using this method. It is unlikely that all of the infected animals will be killed, particularly if the animal does not initially display signs of the disease when examined. Especially because many birds are migratory in nature, it would also be difficult to successfully quarantine the disease.

Another means of protection against the virus relies on medical resources. Although there is no vaccine currently on the market for the H5N1 virus, scientists are in the process of manufacturing one. Richard Webby of St. Jude Children's Research Hospital has "reverse engineered" a version of the H5N1 virus that could be the basis for a vaccine by keeping the parts of the virus that are recognized by the human immune system while immobilizing the critical disease-causing function. The resulting vaccine has been tested on 450 volunteers and produced successful preliminary results. Like most vaccines, to ensure the success of the inoculation, two shots will be needed, each administered about a month apart. The government has awarded a $100 million contract to Sanofi Pasteur of France, to manufacture 20 million doses of this vaccine. However, it is difficult to manufacture because it requires injecting the virus into live chicken eggs. (4)

Antiviral drugs are also being developed as another mode of defense against the avian flu. Tamiflu was developed by Swiss drugmaker Roche and has been touted as the drug that could possibly save the lives of millions should the flu develop into a pandemic. Tamiflu is a neuraminidase inhibitor, allowing it to treat the cause of the flu infection by inhibiting the critical neuraminidase protein on the surface of the virus. Viruses replicate by seizing a cell's genetic machinery to copy themselves and Tamiflu prevents these copies from escaping to infect new cells. It has only been tested against H5N1 in cell cultures and mice but produced successful results in both cases. It has also been proven to work against milder forms of the flu in humans, shortening duration and intensity of a weak strain of the flu virus if administered in the first 48 hours after symptoms occur (5)

However, Michael Osterhold of the University of Minnesota asserts that he is not certain if Tamiflu will work against H5N1 because "the disease goes so quickly to high levels of infection, you might need to take it before you get exposed" (5). Furthermore, the United States only has enough Tamiflu to treat 2.3 million cases, with about 10 million on order. The United States government is trying to stockpile enough medication to treat 20 million people with the drug, but a lot of Roche's production is now committed to other countries that had placed orders earlier. President Bush has responded to this lack of supply by holding a meeting with drug-company executives urging them to speed up their work on vaccines and antiviral drugs. (5)

Another line of drugs, which includes amantadine, targets the M2 protein, "a proton channel found in the viral membrane" (6). Unlike Tamiflu, these drugs are relatively inexpensive and are widely available. However, the potential of these drugs seems to be stunted because it was discovered that China had been giving amantadine to poultry since the early 1900s, creating a strain of the virus that is now circulating in South East Asia that is resistant to the medication and now even more dangerous to humans. However, the strain of H5N1 that is circulating throughout Northern China, Mongolia, Kazakhstan, Russia and Europe is not amantadine resistant. (6)

I think that the frenzy over the avian flu is certainly warranted, especially given the historical context of the 1918 avian flu pandemic in which tens of millions of lives were lost. I also think that it is interesting that a country as powerful as the United States, which seems to be unbounded by its resources, finds its toughest competition in a microorganism that cannot even been seen with the human eye. The United States, and the world in general for that matter, seems to be helpless in the face of this virus. Even though vaccines and antiviral drugs are being developed, there seems to be a lack of preparation and knowledge surrounding this virus. The vaccines are just being developed and the antiviral drugs have only been tested to work only in a Petri dish, mice and on mild strains of the flu. While I realize that we are now taking aggressive measures to speed up the manufacturing of medicines, I hope that it will not be too little too late. A worldwide flu pandemic, such as the one that took place in 1918, would be devastating and its effects would be catastrophic. While it is certainly ironic that an organism that could only be viewed underneath a microscope could potentially rid the world of the human race, it is a serious and unsettling circumstance that hopefully we will not have to grapple with.


1)1918 Flu, Information about the 1918 "Spanish flu"

2)Avian Flu, Information about the avian flu

3) Avian Flu, More Information about the avian flu

Newsweek: October 17, 2005. Volume CXLVI, No. 16. "The Race Against Avian Flu." Jerry Adler and Anne Underwood.

5)Tamiflu, Information about antiviral drugs

6)Avian Flu, Background Information on the avian flu

Panspermia: Not a Porno
Name: Brom Snyde
Date: 2005-11-14 00:18:17
Link to this Comment: 16962


Biology 103

2005 Second Paper

On Serendip

The current debate on the origin of life on Earth usually pits those who believe life emerged out of a primordial soup of molecules and evolved into life as we know it and those who believe that God created life as we know it. A third explanation of the origin of life on Earth is gaining more credence within the scientific community, this theory is called panspermia. The panspermia hypothesis states that life on Earth is a result of living cells from space crashing into the earth and evolving into life as we know it. (1) (2)

The panspermian explanation for life on Earth is not a new one. An ancient Greek philosopher, Anaxagoras, asserted that the all life was the product of "tiny seeds pervading the cosmos." (1) In the latter half of the 19th Lord Kelvin and other prominent scientists promoted the panspermia hypothesis. Kelvin, in 1881, argued:

"when two great masses come into collision in space, it is certain that a large part of each is melted , but it also seems quite certain that in many cases a large quantity of debris must be shot forth and in all directions...should...the earth [come]into collision with another body, comparable in dimensions to itself...many great and small fragments carrying seeds of living plants and animals would undoubtedly be spread through space...we must regard it as probable in the highest degree that there are countless seed bearing meteoric stones moving through space." (3)

Although it seems unlikely that highly organized and improbable life forms like animals and plants would survive spinning through space without protection, the strain caused by extreme temperatures and radiation would kill most complex organisms; scientists now believe that some bacteria can survive in these extreme conditions. In 1908 the panspermia theory gained more credibility when Svante Arrhenius proved that seeds retained their viability when exposed to temperatures near absolute zero and then carefully reheated. (3) Arrhenius' discovery laid the foundation for modern theories of panspermia where dormant bacteria and other organic molecules from space are the origin of the life on Earth.

There are a number of factors that support panspermia as the answer to the origin of life on Earth. The first is the short time span between the formation of the Earth and the appearance of life. Most scientists agree that the Earth formed 4.55 billion years ago and there is evidence of photosynthetic organisms existing as early as 3.85 millions years ago. Photosynthetic bacteria are complex organisms and the likelihood that they are the first living organisms is small due to their complexity. (2) Panspermia explains the earliest living organism known to date being complex photosynthetic bacteria by stating that bacteria may have arrived from somewhere else, where life had a longer time to evolve than it did on Earth. Panspermia expands the timeframe in which life could emerge on Earth, allowing for its development on other planets or even other solar systems and then arriving on Earth via asteroid or comet.

Scientists seeking to discredit the panspermia hypothesis point to the extreme conditions of a voyage through space. They argue that during the entry into the atmosphere, almost all meteorites would get too hot for organic material to survive. They also assert that exposure to ultraviolet light during spaceflight would kill all organic material. (2) (4) Proponents of panspermia point to bacteria's ability to survive in extreme conditions on Earth ( bacteria thrive in thermal vents along the ocean floor and some even live in nuclear reactors) as evidence that they could survive journeys in space. Studies of meteorites reveal that although meteorites experience tremendous amount of friction upon entry into the Earth's atmosphere the heat generated only extends several millimeters deep into the meteor. The interior of the meteorite of would not experience a dramatic temperature rise. Rocks from Mars jettisoned from the surface by the impact of meteorites or comets, called nakhlites, also provide a vessel for the safe transport of organic material as the temperature of the interior of these rocks does not rise above 100 degrees Celsius during their exiting the Martian atmosphere and descent to Earth. (1)

Radiation presents a problem for panspermia advocates. Organic material in meteorites is protected from ultraviolet light if there is thin layer, measuring several microns, between the radiation and the organic material. However, a meteorite traveling through space would be bombarded by different types of radiation. Much of this radiation, like gamma rays, would not be stopped by a layer of rock, rather the rock would cause "showers of secondary radiation within the meteorite" killing organic material. (1) Although some bacteria are very resistant to radiation, the likelihood of their survival would depend on the length of the journey; scientists assert that they live for as long as several decades. (1) The longer the journey of the meteorite the more likely the radiation would kill all organic material.

The panspermia hypothesis offers a different perspective on the origin of life on Earth. The hypothesis is not without its problems, the most prescient being the survival of bacteria in deep space for decades, if not hundreds of years. This concern is not without merit but as scientists develop a greater understanding of the hardiness of living organisms and organic material it seems like there is a possibility that such material can survive in space for extended periods of time. If panspermia is indeed how life was started on Earth it means that we are not alone, across space at one time there existed at least some form of life beyond that of just the Earth. Although panspermia describes where life on Earth comes from, it leaves the larger question of how life started unanswered.

1)"Did Life Come From Another World" by David Warmflash and Benjamin Weiss in Scientific American October 24, 2005.

2) "Panspermia"

3)"Evolution of Life: A Cosmic Perspective" by N. Chandra Wickramasinghe and Fred Hoyle May 2001

4) "Problems with Panspermia or Extraterrestrial Origin of Life Scenarios" from the Intelligent Design and Evolution Awareness Center

Holding off Improbablity: Embalming
Name: Zack Gruna
Date: 2005-11-14 04:26:36
Link to this Comment: 16964

<mytitle> Biology 103
2005 Second Paper
On Serendip

The improbable living body inevitably becomes more probable. When it dies, the elaborate systems crucial to maintaining the body stop working, and the body begins to decompose. Other life forms feast on the remains until the body disappears. Humans, in all our technological splendor, fight the decomposition of our dead bodies through a very temporary and mostly chemical procedure called embalming. In modernity, it is a traditional American practice, though there are many instances of embalming as an important aspect of cultural death rituals in history, the most famous of which being the ancient Egyptian mummifying process. In this paper, I will look at the biological process of decomposition and what embalming does to counteract that process. I also will explore of a few of the moral issues involved in the practice of embalming corpses.

The decomposition of a once-living body is an entirely organic process. That which makes up a human body is the same stuff that serves as the best food/fuel for other living things, and so a dead body is an enormous feast for a whole host of living things. In the human digestive system, various bacteria live symbiotically with their host. The bulk of these bacteria live in the intestine, using the food and passing on digestive benefits to the host human. Once the human dies, the mechanisms that protect the human from that bacteria (the immune system) and the processes that contain the bacteria in the intestinal tract go away, making it possible for the bacteria to spread and actually begin eating the body itself instead of merely what passes through the intestinal tract. (1) Also, enzymes contained within cells will be released, destroying cell membranes and structures. The tightly controlled and functioning system of life is required to keep a body from destroying itself, even if one does not count the vast amounts of other life-forms waiting to eat the body from the inside. Especially destructive are the digestive enzymes, which, when released, begin "digesting" the body itself, thus adding to the decomposition. (1)

The results of all these stages are waste and fluid both within and being expelled from the corpse. The odors of these waste products attract the attention of insects., who also begin to eat the corpse. Maggots will tear through a corpse using a combination of physical (mouth hooks) and chemical (digestive enzymes) in order to use it as both house and fuel. (1) The process of decomposition does not end in here, but we have enough information to continue on with the discussion and examine the technique of embalming.

Embalming in its simplest form involves the removal of blood from the body and the addition of some preservative fluid in its stead. Formaldehyde, or HCHO, discovered as an effective preservative in 1888, is still considered the basis for most fluid arterial embalming. (2) Effective embalming involves the retardation of the decomposition process and creating in the body a life-life look. Formaldehyde is especially effective because it serves many functions: it kills the organisms eating the body from the inside out, destroys the digestive enzymes aiding in decomposition, reacts with proteins to form tough compounds, and also stiffens the tissue, making the body easier to position. (2)

However, embalming does not involve just the substitution of formaldehyde or some similar preservative for the blood in the body. It is a process meant both to avoid the negative effects of decomposition and to create the most life like dead body possible. The embalmer with massage the muscles to alleviate rigor mortis. Then, a small incision is made, usually on the neck, in order to reach the carotid artery and the jugular vein. (3) Usually, blood is drained out of the jugular vein and the preservative pumped in through the carotid artery. The process is never simple, as clots and other such impediments will call for a variety of fluids to be used—anti-clotting agents are needed especially, as an effect of many preservatives is to clot the blood.

The internal organs are treated separately. Instead of arterial embalming, morticians use a process called cavity embalming, which involves injections of various preservatives (usually much stronger than those used in arterial embalming) into the organs. Aspiration, or the removal of other bodily fluids from the stomach and other such cavities is an important step in this part of the procedure. (3) After this is all done, the final steps of embalming involve washing and dressing up the corpse, adding makeup and the like.

Of course, the procedures described here are used in the modern day. Ancient Egyptians, for example, went through a very different process of embalming. Theirs involved a religious belief that the body needed to be prepared in a certain way in order to be ready for a certain kind of afterlife. (4) Modern day embalming, especially in America, is not a religious tradition. It has a curious role in American society. Funeral homes, the businesses that practice embalming corpses, usually explain the need for embalming in two ways. The first reason for embalming is for sanitary and health concerns. The second involves a psychological argument that seeing the deceased body in a good looking state will aid in the healing process and in letting go of the deceased person. (5)

Embalming preserves because it destroys so many of the organic parts of the body in order to make it less useful to those life forms that may want to use those parts. The chemical processes of formaldehyde serve to both destroy enzymes and micro-organisms while creating longer lasting inorganic structures out of organic ones. The living body, instead of going back to the earth, becomes a mess of chemicals that help to preserve the look, if not actual structure, of the body in its living state. I am not attempting to make some kind of argument condemning embalming here, only pointing out that it is a kind of perversion of a natural process.

The American business of undertaking revolves around this process of embalming, because it is what makes the funeral director a possessor of a skill. Without embalming, funeral directors are just guys who sell coffins and graves. (6) Those who defend the open casket viewing and embalming as a tradition may very well have an interest in the business of embalming and restoring corpses. Many people believe that the advancements in embalming techniques and the prominence of the open-casket containing an embalmed and restored corpse as a funeral practice derive from the fact that funerals are a business in America, and, in fact, the process serves no purpose other than to make money for some. The argument ultimately comes down to deciding whether or not the viewing of an embalmed course is psychologically healthier alternative to the opposite, which would be to bury the body as soon as possible to avoid the nastiness of the decomposition process. My own take is that, while funeral homes may be making money somewhat immorally (as all their patrons are grief-stricken and therefore somewhat incapable of making smart consumer choices), embalming as a practice is useful in certain situations. The psychological benefits of a viewing is a complicated issue that cannot be explored with any depth in the few lines I have left in the paper.


Why Is My Arm Twitching!? An Inquiry.
Name: Matthew Lo
Date: 2005-11-14 05:29:07
Link to this Comment: 16965


Biology 103

2005 Second Paper

On Serendip

For several days now, and as I write this paper, a muscle in my left forearm has been twitching vigorously on a regular basis. It is not painful, but I am always able to feel it while it is happening. In general, an episode of spasms begins suddenly and with great rapidity; about ten contractions per second. It then usually slows to irregularly-spaced single spasms, with the occasional double-twitch. All individual spasms are very quick; the contraction and release taking a fraction of a second. The twitch is visible: it appears that a narrow section on the right side of the large anterior muscle (the one that lifts the wrist) is being pulled forward about a quarter-inch. The visibly affected area extends over the inner elbow and about four inches up the upper arm. I had originally attributed the twitch to caffeine or stress, as I find that my left eye twitches in a similar way during periods where I am forced to drink lots of coffee and skimp on sleep. However, for the past few days I have consumed no caffeine and gotten a reasonable amount of sleep. I got some light exercise, and was moderately nervous for a musical performance last night. One possible strain on my left arm was a pain in my wrist from probably straining too hard, playing guitar for a more extended period of time than I am accustomed. Extensive stretching, massage, and more aggressive tactics have done nothing to slow the spasms, indeed, direct pressure on the area will not even stop spasms as they are occurring.

The first step in diagnosing this annoying and increasingly distressing affliction seems to be to determine what is actually twitching. It seems that only the muscle itself has the ability to actually move a part of the body, but of course muscles respond to nerve impulses. Could ligaments or tendons be malfunctioning and triggering these movements? It appears that this would not be the case, as ligaments merely connect bone to bone and tendons muscle to bone. They are made of soft collagenous tissue, and classification of these tissues are based on stiffness of the "crimp" of the tissue and its resistance to load under pressure (1). These characteristics do not seem to suggest the capability of autonomous movement. The same is the case for actual nerves. The action, therefore, must be in the muscle. Something, therefore, is triggering the irregular bonding and release of myosin heads to the actin filaments. This action is also, at a certain level, uncoordinated, because though the movement of the actual muscle is large, there is no visible translation to a bone, moving a limb. Perhaps the "power stroke" of the muscle is so short, and in a small enough section of the muscle that it overcomes the deformation curve of the tendon. However, the timescale of this phenomenon is far shorter than the muscular action I am experiencing. Perhaps the muscle in question serves another purpose. The two strongest possibilities for identity of the offending muscle, based on the line the spasms trace, are pronator teres or the flexor digitalum superficialis (2). There is little reason to suspect the second, as it is a deeper muscle, and much more of it would likely move if it were to misfire. The pronator teres appears exactly the proper size and shape. This muscle originates at the Medial epicondyle of the humerus and at the coronoid process of the ulna, and inserts at the middle of the lateral surface of the radius. In other words, at the very bottom of the humerus, a few inches down the ulna, and between them on the radius, respectively. The muscle pronates and flexes (rotates and bends) the forearm at the elbow. Though it appears that the bulk of forearm flexion is performed by the Brachialis, most pronation is done by the pronator teres, further confusing the question of why my arm remains still when the muscle twitches (3). The muscle is innervated by the median nerve, a common site of nerve compression and repetitive stress syndromes. There exists a pronator teres compression syndrome, but it is fairly rare and its symptoms include pain in the area, weakness in the hand, certain types of palsy in the fingers, and do not include twitching of the muscle (4). None of these apply to my situation.

A visit to a medical reference site querying "muscle twitch" yielded information I had assumed at the beginning of my inquiry. Barring neurological disorders such as Lou Gehrig's disease and Muscular Dystrophy, causes of muscle twitching were simple: caffeine, excessive exercise, stress, a diet deficiency. The former three I was willing to rule out in my situation, but it is possible that there has been a deficiency in my diet. Returning to institutional food has greatly increased the proportion of meat in my diet, which had been significantly reduced during the summer, and it seemed particularly high in the past week. Further research suggested that spasms and cramps could be caused by a calcium deficiency resulting from high protein or phosphate intake. A deficiency in pantothenic acid (Vitamin B) were pointed to as a cause, but several prime sources of the vitamin were part of my diet in the period in question. A high Magnesium-to-Calcium ratio in the body was another cause. It is true that most recently, green vegetables and legumes, the major sources of magnesium, had not been in adequate proportions in my diet, but this would presumably result in, if anything, a low Mg/Ca ratio Consuming foods containing lactic acid was pointed to as a possible strategy (6). In the end, it was unclear exactly what could be done on a dietary level to correct this ratio, as consuming more of one mineral would block absorption of another in a complex web, and it would be impossible to be certain of the proportions in my body without knowing the proportions in the foods I ate, without having kept careful track of what I had eaten in the period in question.

Would there, then, be anything that could be done in the short term? It seems to stand to reason that the malfunction of myocin in the muscle would be triggered by the synapses of a nerve going haywire. Is there any way that the functioning of a cluster of nerve cells could be directly impacted? A relationship between electrical pathways in the body and acupuncture came to mind. Most charts of acupuncture meridians that I was able to find related the acupoints to organs, as opposed to specific muscles or limbs, which seemed like a dead end. This was interesting, however, as it was indicated that Eastern medicine traditionally conceived of disease as a collection of symptoms rather than a unified state of the body, which would suggest that their treatment strategies would target various body aches outside of the major organs in the trunk or head (8). Another article indicated that "The change of electric activity is part of signal transduction and can precede anatomical change," but that some electromagnetic patterns in the body mapped by a SQUID (Superconducting Quantum Interference Device) are consistent with the meridian system, but not necessarily "any major nerve, lymphatic, or blood vessel" (9). The author goes on to note that "An "annealing" mechanism may play a role in acupuncture and related techniques: Small perturbations at singular points elicit a "shock" to the system - activates and shakes the biological system out of its abnormal and unstable state. After activation, the system has a better chance to settle at a normal, more stable state." It seems likely that acupuncture could have an effect on my own particular malfunction, if it is in fact related to the electrical impulses in the muscle, but it seems that to find out exactly how would require the involvement of a specialist, or, as the web seems to indicate, the purchase of a book.

In the end, this particular spasm episode will likely soon come to an end, but a few questions still remain unanswered in my mind. First: if, for instance, the spasms were caused by a nutritional deficiency, why would that macro deficiency manifest itself in one section of the body for an extended period of time? Second: another article outlining the system of nerve impulses involved in a reflex reaction demonstrated the level of communication necessary to return a reflex impulse to its point of origin. What if my left pronator teres or its median nerve thought that it was receiving an impulses and was actually responding normally? If so, what could this false impulse have been caused by? Most of my confusion arises from the specificity in manifestation of a generalized explanation. What is so different about this particular assembly?

1) Notes for a U-Michigan biomechanics course

2)Contents of upper limb and back, drawings of macro anatomical assemblies

3)Upper Extremity Muscle Atlas

4)eMedicine, Hand and nerve compression syndrome overview

5)National Institutes of Health, NIH Reference Site

6)Acu-cell, Nutritional causes of muscle spasms and cramps

7)Acu-cell, nutritional mineral ratio primer

8)The Med-Com Resource, Acupuncture primer

9)The Meridian System and the Mechanism of Acupuncture, Article on acupuncture research

Dispersion of Humans
Name: Iris
Date: 2005-11-14 15:47:53
Link to this Comment: 16980


Biology 103

2005 Second Paper

On Serendip

Segregation has been, and can be, seen occurring wherever from lunch tables to areas in cities. Understanding why this occurs is highly complicated due to the many factors that lead to people living in the midst of others like themselves. Among these factors are externalities that have caused certain people to be found in a given area. This reasoning can account for what looks like global segregation. It is obvious that people in a given geographic area have a set of characteristics that differentiates them from other parts of the world. What factors have caused these differences? In order, to understand the factors that may have influenced human variation a look at Homo sapien evolution is the first step.
The origin of the modern humans is a topic that has been looked at by scientist in many fields such as molecular biologists and anthropologists. These scientists have come up with differing time lines on human evolution. Molecular biologists believe that "modern humans evolved in Africa about 200,000 years ago, from where they migrated throughout the rest of the world." (1) On the other hand, Anthropologists believe "modern humans evolved on a broad geographic front, absorbing rather than replacing" (1) primitive humans. Therefore, without any intermediary theories if one group of scientists is right then the second is found in error so intensive research has been done on this matter. In 1987, a conference took place at the University Of Cambridge, England to discuss evolutionary theory. A population geneticist, a demographer and an ecologist all supported the molecular biologists statement. Why does it matter how humans evolved? Because depending on the theory believed, there are implications about human dispersal across the globe.
Let us begin by looking at the molecular biologists' theory. Their statement suggests that humans all came from Africa and replaced other humans as we dispersed across the globe. There is only one point of origin and so extensive migration would have ensued for the present distribution of humans. Evidence of this possibility was seen at Klasies River Mouth where human fossils where found to be between 115,000 and 80,000 years old (1). Assuming this, we all come from the same root and so have similar genes. Then why do we differ so much in characteristics? The factors that can explain this comes from the separation of peoples carrying along certain genes that continued to be passed down along the given lineage. Even though, the same genes were present certain genes manifested there self more often and thereby some genes may have been turned off. Natural selection played a major role, as well, because some people are unable to survive the changes in their environment as they move across different terrain, therefore, certain genes die along with them. An example of this is melanin, which "play a major role in the quenching of free radicals produced by ultraviolet radiation" (2). It is manifested in the color of our skin. Africans have dark complexions since they are where sun exposure is greatest. This suggests that as populations moved from Africa their bodies adapted to less sun exposure for survival
Before the evidence at Klasies River Mouth, anthropologists believed that humans across the globe independently evolved at the same time without interactions with one another. The best fossil records were found throughout the eastern hemisphere of the world, evidence that showed modern humans had many points of origins. Assuming this theory, we cannot talk about dispersal or movement as the reasoning for the striking variation between people in the world. In this case, each group evolved on its own with its own gene pool in given locations so the disparity is best explained by the isolation of these groups for a large number of years.
The theories mentioned give us a good idea as to some of the factors that have affected human differences in the world. They include humans carrying certain genes and moving with them in a group, natural selection, genes being turned off or not recurring in a given population, and human isolation.


1) Lewin, Roger. Africa: Cradle of Modern Humans, Science, New Series, Vol.237, No. 4820.
2) Cesarini, J.P. M.D. Melanins and their possible roles through biological evolution, Advances in Space Research, Vol. 18, Issue 12, 1996.
Campbell, Neil and Reece, Jane. Biology. Benjamin Cummings San Francisco, CA, 2002.
Pritchard, Jonathan. Genetic Data and the African Origin of Humans, Science, New Series, Vol. 274, No. 5292.

ADHD and Stimulant Medication
Name: Gillian St
Date: 2005-11-15 20:25:16
Link to this Comment: 17009


Biology 103

2005 Second Paper

On Serendip

Attention-Deficit Hyperactivity Disorder -- more commonly known as ADHD -- is a disorder that afflicts an estimated 3-6% of school-age children (1). Usually arising between the ages of 3 and 5, this disorder is characterized by atypically high levels of locomotor activity and an inability to stay mentally focused on a single task for more than a few minutes. ADHD patients often act impulsively, ignoring social norms and rules and behaving in a way that is considered obnoxious, which may be socially debilitating, especially in younger children whose peers don't understand their disorder. All of the direct symptoms of ADHD are unified by one characteristic: an inability to inhibit behavior. ADHD has no effect on an individual's level of intelligence or emotional stability, however; it only disrupts the patient's ability to focus and be productive. A common misconception about ADHD is that it directly causes children to act aggressively and defiantly, but in fact, aggression and defiance are exhibited in only about 35% of people with ADHD. In some cases, the symptoms of ADHD may be extinguished during the natural course of development; in other cases, however, the symptoms often continue on into adolescence and even adulthood.

In order to be diagnosed with ADHD and medically treated by a licensed psychiatrist, a person must have exhibited the symptoms before the age of 7. In addition, the symptoms must be pervasive (evident in at least two separate settings), and must have led to some sort of academic or social difficulty. Males are diagnosed with ADHD 3-9 times as often as females, but researchers are reluctant to attribute this to males having a higher susceptibility to the disorder. Rather, this discrepancy is most likely a result of the symptoms being simply overlooked in females; especially among young children, boys with ADHD are more easily noticed because their symptoms are more flagrant (6).

Researchers insist that there are no known environmental causes of ADHD. Scientists used to think that parents could decrease the likelihood of their children developing ADHD by controlling how much TV they watched and their sugar intake. People also thought that a stressful home life or a poor school environment could cause the disorder (3). These hypotheses have been disproven as new techniques of studying ADHD have developed; it is now known that ADHD is in fact caused by chemical levels in the brain. However, there is an element of heredity; ADHD runs in families, and in recent studies of identical twins, researchers found that if one twin has the disorder, the other is almost guaranteed to have it as well (6). In addition, adopted children with ADHD are lilely to have a biological parent with the disorder; adopted children exhibit the symptoms regardless of whether their adoptive parents have the disorder. This suggests that the development of ADHD is not influenced by social factors (6). Prenatal teratogens (chemicals taken in by a mother when pregnant that are harmful to the developing fetus) have also been linked to hyperactivity and inattention symptoms, in particular those involving long-term exposure, such as alcohol and nicotine (6).

New technology has recently enabled scientists to look at the inner workings of the brain. Scientists have used PET (positron emission tomography) scans to determine that the frontal cortical regions of the brain in particular are responsible for locomotor functions, concentration, and inhibition, all of which are involved in ADHD symptoms (1). Two specific areas that is most consistently implicated as being responsible for these functions are the prefrontal cortex and the basal ganglia. Other types of brain scans have shown that ADHD patients have significantly reduced electrical and blood flow activity in these two regions. In children with ADHD in particular, there is less brain activity in the left sensorimotor area of the cortex, which (because of the physical functions affected by the frontal cortex) would result in less control over physical activity (6). This would explain why children with ADHD are especially hyperactive.

In the basal ganglia, scientists have noticed significantly increased levels of dopamine -- a neurotransmitter which influences movement, attention, and emotion -- in people who have ADHD (7). This discovery has led to the use of dextroamphetamines and methylphenidates as treatments for ADHD. Both of these types of medications are stimulants, which may seem counterintuitive, considering ADHD patients' already-hyperactive disposition. However, stimulants are the most consistently helpful form of medication for people with ADHD. Dextroamphetamines and methylphenidates moderate the noradreneric (adrenaline-producing) and dopaminergic (dopamine-producing) systems of the endocrine system, thus bringing the dopamine levels in the basal ganglia and the electrical and blood flow levels in the frontal cortex back to normal (1).

The most commonly-prescribed methylphenidate is Ritalin; each year, approximately 2 million children in the United States take Ritalin to mask their ADHD symptoms (1). Approximately 4 million children are prescribed some other type of methylphenidate medication (4). Ritalin works by blocking dopamine transporters, therefore decreasing the amount of dopamine in the basal ganglia. Because dopamine affects movement and attention, Ritalin helps to decrease hyperactivity and promote concentration and focus by giving the ADHD patient more control over these functions (2). Adderall, the most commonly-prescribed type of dextroamphetamine, has recently become much more popular, because it remains active in the body for longer than Ritalin does, and according to some patients, has less of a "drop off effect" (4).

One main problems with these types of medication is the increasing rate of recreational use. Dextroamphetamines and methylphenidates have the same stimulating effects on healthy people without ADHD as they do on ADHD patients, so when taken in heavy doses without prescription, they can have the same basic effect as cocaine or other very potent stimulants. Ritalin and Adderall are easy to obtain, given the fairly high number of school-age children that have been prescribed these medicines to treat their ADHD. Recent surveys show that about 2.5% of 8th-graders, 3.4% of 10th-graders, and 5.1% of 12th-graders have abused Ritalin (2). Another problem with the use of stimulants to treat ADHD is the emergence of psychotic symptoms in some ADHD patients. One study at a clinic in Canada involved 98 children with ADHD who had been placed on some type of stimulant drug and 94 children who had ADHD but had never taken stimulant medication. Nine percent of the children taking stimulants exhibited psychotic symptoms of some level of intensity, whereas none of the other children exhibited these psychotic symptoms at all (5). Clearly the side effects of these stimulants need to be reexamined, but for now, these problems have resulted in media coverage and lawsuits against stimulant manufacturers.


1)Brain Imaging Data of ADHD

2) NIDA InfoFacts: Methylphenidate (Ritalin)

3)What Causes AD/HD?

4)Stimulant Drugs for ADHD and ADD

5)Confirming the Hazards of Stimulant Drug Treatment

6)Berk, Laura E. Child Development. Boston: Pearson Education, Inc., 2003.

7)Myers, David G. Psychology. New York: Worth Publishers, 2001.

Splenda: Super Sweetner of Health Hazard?
Name: Sara Koff
Date: 2005-11-16 15:05:34
Link to this Comment: 17019


Biology 103

2005 Second Paper

On Serendip

Splenda, best known for its marketing logo, "made from sugar so it tastes like sugar,' has taken the sweetener industry by storm. Splenda has become the nations number one selling artificial sweetener in a very short period of time(2).

Splenda is the brand name for the ingredient sucralose. It is made through a multi-step process that starts with sugar and converts it to a no calorie, non-carbohydrate sweetener. The process selectively replaces three hydrogen-oxygen groups on the sugar molecule with three chlorine atoms. In the case of sucralose, the addition of chlorine converts sucrose to sucralose, which is essentially inert. The result is a stable sweetener that tastes like sugar, but without sugar's calories. After consumption, sucralose passes through the body without being broken down for energy, so it has no calories, and the body does not recognize it as a carbohydrate (1).

There is no question that sucralose (Splenda) starts off as a sugar molecule, it is what goes on in the factory that is concerning(2). Sucralose is a synthetic chemical that was originally cooked up in a laboratory. In the five step patented process of making sucralose, three chlorine molecules are added to a sucrose or sugar molecule. A sucrose molecule is a disaccharide that contains two single sugars bound together; glucose and fructose. Samantha Heller, MS, RD, says, "Saying Splenda is made from sugar is like taking the round wheels off a car and putting on square wheels. Is it still a car? Yes. But can it still perform like a car? No -- and what's more we don't know what's going to happen when people try to 'drive it' cross country," (4)

The chemical process to make sucralose alters the chemical composition of the sugar so much that it is somehow converted to a fructo-galactose molecule. This type of sugar molecule does not occur in nature and therefore your body does not possess the ability to properly metabolize it. It is not that Splenda is naturally zero calories. If your body had the capacity to metabolize it then it would no longer has zero calories(4).

While all these complex chemical processes may not matter much to your taste buds, experts say it takes on a new and more important meaning as Splenda will begin to be included in many different products including diet soda and various baked goods. The biggest fear is that sucralose will be everywhere and used in everything when people still are not aware of what they are and are not getting. It is also important to note that artificial sweeteners are a relatively new invention and that there is no data as to how they interact with each other especially in large amounts(2).

So is Splenda safe? The truth is we don't know yet. Not only are we unaware of the long term affects of artificial sweeteners, research in animals have shown that sucralose can cause problems. These include an enlarged liver and kidneys, reduced growth rate, decreased red blood cell count and decreased fetal body weights(3). So the reality is that we are the guinea pigs for Splenda.

Observational evidence shows that there are side effects of Splenda, including skin rashes/flushing, panic-like agitation, dizziness and numbness, diarrhea, muscle aches, headaches, intestinal cramping, bladder issues, and stomach pain. Most of these observations have been found in people believed to have an allergy or sensitivity to sucralose. But no one can say exactly to what degree Splenda is affecting the rest of us(2).





Mutations, Evolution, Questions and Faith
Name: Norma Alts
Date: 2005-11-21 20:20:48
Link to this Comment: 17124

<mytitle> Biology 103
2005 Second Paper
On Serendip

How do creationists treat mutations - random genetic changes that can result in changing traits or characteristics? At the core of evolutionary theory is the idea that organisms with favorable mutations flourish and those with negative mutations are weeded out through natural selection; when creationists that mutations occur, how do they refute the story of evolution? What is different about these creationists' methods of mobilizing science?

In this paper, I will analysis two online sources - "Scientists Speak Out Against Mutation," from the Creation-Evolution Encyclopedia and "Can genetic mutations produce positive changes in living creatures?" from Christian Answers - that represent creationist arguments about mutations that I found in my survey of websites on this topic. I chose to limit the number of web pages so that I could closely analysis the arguments each page. Drawing on arguments made by biologists who are proponents of evolutionary theory, I attempt to respond to creationists' concerns from this perspective. Both sources mobilize science to support fundamentalist Christian explanations of nature. So how do the non-Christian sources differ? As this paper will illustrate, these explanations ask more complicated and more extensive questions than creationists do. Finally, speaking to the heart of this question of what makes for compelling and useful explanations of the natural world, my paper will conclude that for those inclined towards evolutionary explanations, continued inquiry beyond seemingly suitable explanations is at the heart of good science.

My first source is an entry from the online Creation-Evolution Encyclopedia, which purports to be "the most comprehensive source of scientific facts and statements on origins." The website that I analysis is drawn from a book authored by Vance Ferrell; little information is available about the Christian publishers, Pathlights. The Encyclopedia seeks to disprove evolutionary theory with scientific tools - to use comprehensive scientific information to support creationism. The website aims to lead people towards "happier, better lives" as they learn "the truth about origins." (1) The authors do not state that these benefits will come from divine favor; rather, they claim that evolutionary theory lowers morality and stress that its scientific fallacies cloud clear, rational thought and discourse about life. (2) Apart from the moral goals, their aims are, in many senses, scientific. The idea that scientific methods of thinking are valuable intellectual tools is widespread; one reason Bryn Mawr College requires students to study natural sciences is to cultivate "facility with... techniques of scientific inquiry [and] logical reasoning." (3) Indeed, this course is designed to be an ongoing conversation in which all benefit from each others' discourses. (4)

Rather than outlining a scientific argument, however, the sections I draw on , entitled "Scientists Speak Out Against Mutation," contain quotations - the majority of which the site's authors claim come from people who are "not known to be creationist[s]" - that raise questions about the validity of evolutionary theory. The compilers intend to use scientists' own words to demonstrate that evolution does not make sense. This site argues that mutations are so rare that evolution is mathematically impossible, and that mutations are almost always harmful. Further, it contends that there is no evidence that mutations account for the emergence of new species or of increasing complexity - that even if mutations could change a species no one has observed the formation of new life from mutations. (5), (6)

At first glance, some of these contentions seem compelling. Certain scientific sources, however, have found conflicting information about the probability and benefit of mutations, and their ability to create change. These arguments are based on greater engagement with biological processes than presented in "Scientists Speak Out Against Mutation" - which simply complies quotations, most of them more than 40 years old, out of context. In the next paragraphs, I will demonstrate this point by explaining and analyzing evolutionary counter-arguments.

Most mutations, Biology textbook editors Neil Campbell and Judy Reese argue, are harmless - and many harmful mutations are not passed on genetically. Some mutations adversely affect organisms, but others are beneficial. (7)One way to account for increasing complexity occurs when parts of an organism shifts functions. The bacterial flagellum, which acts as a propeller, is composed of 30 proteins that must be arranged in a precise structure. While biologist Michael Behe argued that this organelle's complexity pointed towards intelligent design, other scientists have argued that the proteins initially had other functions - some independently acted as a pump for poising other cells. (8), (9) Lighter bones originally enable bird ancestors to climb trees; as wings gradually emerged as a result of random genetic mutations, flying was possible because of changes to bones. ((7)

Furthermore, species changes emerge through mutations to hox genes, which direct the development of body parts. Evidence suggests that around 520 years ago a duplication of these genes produced the first vertebrates; a second duplications, which about 425 years ago, allowed for even more complexity, such as jaws and limbs. Changes to the timing of development through hox mutations can alter form of the adult species. Some salamanders are able to live in trees because their foot growth ends sooner than salamanders that live on the ground. Shorter limbs and more webbings means they can climb up trees.

But what about The Creation-Evolution Encyclopedia's concern that no one has observed increasing complexity? An extensive article about flagella emergence suggests that scientists evaluate explanations based on an explanatory model's identification of an ancestral protein with a different function, the probability that this protein might change function, and the systems in place to support the new function's continuation. (10) Explanations are evaluated, in other words, based on their plausibility - this source looks beyond observations to different ways of asking questions and evaluating information.

My second source uses a different format to question scientific explanations of mutations. A section of the website Christian Answers, a comprehensive resource on Christian issues, the creationist sections attempt to "[win] people of all ages... to the Lord" and "[help" great numbers of Christians... in many ways throughout the world." The article "Can genetic mutations produce positive changes in living creatures?" purports to use "scientific tools of measurement and observation" to determine the actual state and origin of the world. (11) Like the Creation-Evolution Encyclopedia, it mobilizes science to support Creationism, although it uses original prose rather than a compilation of quotations. It also differs by focuses more directly on the benefits of divine favor - salvation.

The article contends that scientific research shows that mutations do not account for the chance emergence of positive traits. Rather, the prevalence of negative mutations demonstrates that the natural world is increasingly chaotic and the human genetic code will eventually become "gibberish." "Christian hope stands as the only light" in the darkness and destruction inherent in the laws of nature - in the increasing entropy of the universe.

As an evolutionary response to my first source might argue, mutations can explain the development of positive traits. The contention about increasing entropy is related to the Second Law of Thermodynamics, which states that all closed systems tend towards greater entropy, or disorder, over time. (12) However, organisms are not a closed system - the interact with the rest of the world and universe - and so increasing disorder in an organism is not necessary, as long as the universe becomes increasingly chaotic. (9) This argument engages with (and cites explicitly) the scientific principle that it is based on by pointing to the Second Law's limit to closed system. Furthermore, life makes use of probability - of falling apart - to draw out energy. Mutations that move an organism towards complexity do not require a radical increase in the amount of order in the universe. (12) Sometimes organisms release less ordered forms, such as heat, than the materials they ingest. (13) These explanation engage with the particular biological processes - they look at whether order actually increases based on how organisms operate and at what organisms emit.

Good scientific explanations engage with the particulars of systems and scientific rules they analyze, and look towards new and complicated ways of evaluating information. Engaging with creationist arguments can provide a powerful stimulus for doing so. Many individuals on both sides of the debate about evolution are embedded in their beliefs and extremely skeptical of any arguments from the other side. In my early stages of research I found myself unable to explain how evolution could account for cross-species change despite considerable efforts. My faith in the theory of evolution, rather than specific questions that I had about creationists' arguments, drove me to continue to look for explanations. However, I then could look at creationist and evolutionary sources, and compare the rigor of their arguments. Some make creationist arguments for non-scientific reasons, but both sources I examine purport to look for scientific explanations. If one uses these methods, one should be open to changing one's answers about evolution. My experience and sources suggest, however, that even if one is grounded in a set of beliefs one can engage with more rigorous scientific methods and questions. And perhaps, at least for some, experiences with scientific methods will lead to a greater willingness to question their personal evolutionary articles of faith.

1) the homepage of The Creation-Evolution Encyclopedia
2) Why this Encyclopedia , the mission statement of The Creation-Evolution Encyclopedia
3) The Bryn Mawr College course catalog
4) Course presumptions for Biology 103 at Bryn Mawr College, from the Serendip website
5) Part one and 6) part two of quotations complied to demonstrate that mutations undermine evolutionary theory, from the Creation-Evolution Encyclopedia
7) Campbell, N., & Reece, J. (2005). Biology. San Francisco, Pearson Education Inc., 459-486.
8) An article about the debate between proponents of intelligent design and evolution, from the New Yorker
9) A special report on intelligent design and evolution from the American Institute of Biological Science's educational website
10) An article about the origin of the flagellum from a website that responds to arguments about intelligent design
11) An article about mutations from, an extensive evangelical site
12) A wikipedia article on the Second Law of Thermodynamics
13) Lecture notes from a biology course at West Virginia University

Dispersion of Humans
Name: Iris Mejia
Date: 2005-11-21 21:05:02
Link to this Comment: 17129


Biology 103

2005 Second Paper

On Serendip

Segregation has been, and can be, seen occurring wherever from lunch tables to areas in cities. Understanding why this occurs is highly complicated due to the many factors that lead to people living in the midst of others like themselves. Among these factors are externalities that have caused certain people to be found in a given area. This reasoning can account for what looks like global segregation. It is obvious that people in a given geographic area have a set of characteristics that differentiates them from other parts of the world. What factors have caused these differences? In order, to understand the factors that may have influenced human variation a look at Homo sapien evolution is the first step.

The origin of the modern humans is a topic that has been looked at by scientist in many fields, such as molecular biologists and anthropologists. These scientists have come up with differing time lines on human evolution. Molecular biologists believe that "modern humans evolved in Africa about 200,000 years ago, from where they migrated throughout the rest of the world."(1) On the other hand, Anthropologists believe "modern humans evolved on a broad geographic front, absorbing rather than replacing" (1) primitive humans. Therefore, without any intermediary theories if one group of scientists is right then the second is found in error so intensive research has been done on this matter. In 1987, a conference took place at the University Of Cambridge, England to discuss evolutionary theory. A population geneticist, a demographer and an ecologist all supported the molecular biologists statement. Why does it matter how humans evolved? Because depending on the theory believed, there are implications about human dispersal across the globe.

Let us begin by looking at the molecular biologists' theory. Their statement suggests that humans all came from Africa and replaced other humans as we dispersed across the globe. There is only one point of origin and so extensive migration would have ensued for the present distribution of humans. Evidence of this possibility was seen at Klasies River Mouth where human fossils where found to be between 115,000 and 80,000 years old (1). Assuming this, we all come from the same root and so have similar genes. Then why do we differ so much in characteristics? The factors that can explain this comes from the separation of peoples carrying along certain genes that continued to be passed down along the given lineage. Even though, the same genes were present certain genes were manifested more often and thereby some genes may have been turned off. Natural selection played a major role as well; because some people are unable to survive the changes in their environment as they move across different terrain, therefore, certain genes die along with them. An example of this is melanin, which "play a major role in the quenching of free radicals produced by ultraviolet radiation" (2). It is manifested in the color of our skin. Africans have dark complexions since they are where sun exposure is greatest. This suggests that as populations moved from Africa their bodies adapted to less sun exposure for survival.

Before the evidence at Klasies River Mouth, anthropologists believed that humans
across the globe independently evolved at the same time without interactions with one another. The best fossil records were found throughout the eastern hemisphere of the world, evidence that showed modern humans had many points of origins. Assuming this theory, we cannot talk about dispersal or movement as the reasoning for the striking variation between people in the world. In this case, each group evolved on its own with its own gene pool in given locations so the disparity is best explained by the isolation of these groups for a large number of years.

The theories mentioned give us a good idea as to some of the factors that have
affected human differences in the world. They include humans carrying certain genes and
moving with them in a group, natural selection, genes being turned off or not recurring in a given population, and human isolation.


[1] Lewin, Roger. Africa: Cradle of Modern Humans, Science, New Series, Vol.237, No. 4820.
[2] Cesarini, J.P. M.D. Melanins and their possible roles through biological evolution, Advances in Space Research, Vol. 18, Issue 12, 1996.
Campbell, Neil and Reece, Jane. Biology. Benjamin Cummings San Francisco, CA, 2002.
Pritchard, Jonathan. Genetic Data and the African Origin of Humans, Science, New Series, Vol. 274, No. 5292.

Ethanol, Biodiesel, and other Improbable Things
Name: Zach Withe
Date: 2005-11-29 00:15:54
Link to this Comment: 17207

<mytitle> Biology 103
2005 Second Paper
On Serendip

Ethanol, Biodiesel, and other Improbable Things

Ethanol, Biodiesel, and other Improbable Things

Zach Withers


We've discussed how life tends to use carbohydrates and lipids as their main sources of energy, and how man-made machines tend to be powered by hydrocarbons. The process by which each releases energy is similar – the breakdown of hydrogen-carbon bonds in the presence of oxygen and the recombination of these elements into more probable molecules, specifically carbon dioxide and water. The fact that hydrocarbons and carbohydrates store and release energy in a similar manner is not surprising. After all, the former is essentially a compressed and then broken down form of the latter. This paper will look at how organic matter becomes hydrocarbons, why life powers itself on carbohydrates instead of hydrocarbons, and current attempts to run our machinery on alcohols and lipids, cutting out the several-thousand-years-of-subterranean pressure middleman.

            Hydrocarbons are formed from carbohydrates and lipids in a two-step process. Dead organic matter, if exposed to the elements, quickly decomposes and dissipates. However, if it is quickly buried in an oxygen-poor environment, the improbable organic molecules will still break down, but their constituent elements have nowhere to go. Given enough time, the weight of material piling on top of the organic matter will compress it into large, irregular molecules called Kerogens, consisting largely of long hydrocarbon strings. As pressure and heat continue to build, Kerogen itself tends to become unstable and break down, forcing its hydrocarbon strings out into the surrounding rock. These string, which being rather light tend to rise toward the surface, are what are extracted as petroleum.[2]

            It's worth noting just how similar these hydrocarbon chains really are to the energy sources formed by life. The best comparison is between hydrocarbons and lipids, or more specifically between hydrocarbons and fatty acids, the subunits of which lipids are composed. Hydrocarbons are simply regular chains of carbon and hydrogen. Fatty acids are regular chains of carbon and hydrogen with what might be called a "knotted end" – a carboxyl group which binds to larger organic molecules. [4] In other words, life, in its infinite wisdom and complexity, creates something almost identical to what you get when you dump a bunch of carbon and hydrogen underground and press on it for several million years. Like the sugar that falls out of the sky (at a very slow rate), life stores its energy in the same form inanimate nature tends to store its own energy in. It just puts the atoms together a great deal faster.

            This explains why there is such great promise in non-fossil fuels. There is nothing special that happens either in a living body, or deep under the Earth. A process which leads to carbons and hydrogens being linked in a chain is just as good as any other process which does the same. In fact, Rudolph Diesel, creator of the Diesel engine, intended his engine to run on peanut oil. [11] It was only later that the engines were modified to run on "diesel fuel", made up of petroleum-derived heavy hydrocarbons instead of lipids, and differing only in that it is slightly less viscous. Using the process of transesterification, it is possible to modify lipids into a slightly different form with a slightly lower viscosity, thus creating "biodiesel", a substance slightly chemically different from petroleum diesel, but functionally identical, and capable of burning in petroleum-tuned diesel engines. [3, 12]

The question is, where could be possibly get enough lipid from to take the place of the years worth of collected organic matter we burn daily? The good intentions of grease car owners aside, used fryer oil is not going to deliver us from our fossil fuel crunch. "Virgin" oil from plants grown specifically to be modified into biodiesel is another avenue which is being pursued to some success – 40 to 50 gallons of oil can be squeezed from an acre of soybeans, or 110 to 145 from an acre of rapeseed (canola). [3] However, there is great deal of controversy over whether it actually takes more energy to grow, harvest, and process these crops than is gained from burning the resultant fuel. [10]

What may turn this process from a sidelight into a full-fledged hydrocarbon replacement, however, is the advent of algae biodiesel. Certain varieties of algae are up to 50% oil by mass. A 1 acre tank of one of these algae varieties could yield between 10 and 20 thousand gallons of biodiesel. Additionally, unlike other sources of feedstock which must be grown on productive land, precluding the use of that land for other things, oil-heavy algae grows best wherever there's plenty of sunlight – the middle of the desert, for example. As for what to feed the algae, many of these varieties will live quite happily on agricultural waste. [3]

From a chemical standpoint, the use of ethanol as a replacement for lighter hydrocarbon mixes such as gasoline is probably more interesting, specifically because ethanol is so chemically different from the hydrocarbons it replaces. Ethanol, the same alcohol present in alcoholic beverages, is a small and simple molecule, C2H6O. [1] Remove the oxygen atom, and you have ethane, one of the lightest hydrocarbons, a gas at room temperature. [5] Ethanol, however, is not only a liquid, it is a liquid denser than gasoline. This happens for the same reason water is so dense for its molecular weight – oxygen is "grabby". Ethanol is a somewhat polar molecule, which leads to the oxygen end of one molecule drawing the non-oxygen end of the next one in, and drawing the whole complex of molecules into close formation. The result is that although a single ethanol molecule is much lighter than a heavy hydrocarbon, a given volume of ethanol is heavier than an equivalent volume of heavy hydrocarbons. From an energy/probability standpoint, however, a single ethanol molecule is much more probable than a single heavy hydrocarbon molecule, and a liter of ethanol is also more probable than a liter of heavy hydrocarbons. [9, 5] The presence of oxygen in ethanol makes it a much more probable molecule than an oxygenless hydrocarbon. Hydrocarbons tend to break down in the presence of oxygen. Ethanol, on the other hand, is somewhat more resistant – it already has oxygen in itself. Ethanol, in fact, is the byproduct of glucose breakdown in the absence of oxygen. Again like our sugar from the sky, ethanol will spontaneously form from a bunch of sugar in an airtight box. It will just happen very slowly. The proper enzymes speed up the process. [8]

The chemical similarities of lipids, hydrocarbons, and alcohols raise some interesting questions about the construction of life. Could life have evolved to synthesize hydrocarbons rather than lipids, or burn ethanol rather than carbohydrates? Well, in the last case, the answer is obviously yes. Ethanol is synthesized by yeast as a byproduct of anaerobic respiration, and can be broken down and used for energy by animals, albeit with well known side effects. [1] A slightly different evolutionary path, it seems, could easily have brought us to a point where our bodies were constructed of entirely different molecules, and yet accomplished the same functions.



1. Wikipedia on Ethanol -

2. UK Offshore Operators Assn: The Origins of Oil and Gas -

3. Wikipedia on Biodiesel -

4. Wikipedia on Fatty Acids -

5. Wikipedia on Alcanes -

6. Wikipedia on Diesel Fuel -

7. University of Cincinatti: Cellular Respiration -

8. Enzyme Development Corp: Fermentation Ethanol -

9. Energy Density of Ethanol -

10. Biology News Net – Ethanol and Biodiesel not Worth the Energy -

11. Yokayo Biofuels: History of the Diesel Engine -

12. Wikipedia on Biodiesel Production -

Vampires and Porphyria: A Closer Look at Scientifi
Name: Scott Shep
Date: 2005-11-29 14:18:23
Link to this Comment: 17212


Biology 103

2005 Second Paper

On Serendip

In a eureka-driven frenzy, all the rational people of the village gathered their New York Times Articles and pitchforks! The mob became ferociously scientific and their minds were on the source of that fictional horror that continued to besmirch the world of facts: the vampire. They stormed the modern village shouting, "It is Porphyria! Praise God! We can lay the legend to rest! Vampires were victims of a medical disorder called Porphyria". In ardent passion they pierced complexity with stakes of Scientific simplification, and hoped that perhaps this time things would be resolved for good.

Before being accused of hypocrisy, it is important to say that this bit of introductory sarcasm only aims to show that science and rationalism does not protect human beings from their inclinations to simplify situations so that they can Know with certainty something about the world. A popular trend in modern science has been to simplify the legends and folklore of many cultures by offering new explanations that gain legitimacy in popular opinion because they ascribe to the aura of Science—this aura connotes a close proximity to truth, discretion, and progress whether it is achieving these goals or not. Recently, the idea that vampire myths originated from the logical beginnings of a disease called Porphyria has become popularized. Although the parallels between certain symptoms of the disease and characteristics of the vampire figure are clear, certain scientific representations of the Porphyria theory, namely the listed New York Times article, ignore cultural and historical information about myth-making in order to keep their scientific theory suggestive and alluring rather than accurate.

Porphyria is actually a general name for a collection of more specific diseases that are related to a surplus of porphyrins or antecedent porphyrin substances that collect in the body. These dangerous porphyrins and antecedent porphyrin substances, result from problems that occur in the eight step process to create the very important molecule, heme. Heme is essential for creating hemoglobin—a molecule in red blood cells that facilitates the transportation of oxygen. (1) Ordinarily, different enzymes trigger very specific reactions in a very specific order to finally create heme, but when one of these enzymes is abnormal or absent, the uncompleted substances collect in harmful amounts. Depending on the specifics of the malfunctioning enzyme, the effects vary in type and intensity. One form in particular more commonly called, Gunther's Disease has the most distinct vampire correlates, but most forms share characteristics of the mythic creature. (5)

One odd characteristic about Porphyria is that the deleterious porphyrin substances are activated the in the presence of sunlight. The wavelengths of sunlight excite the toxins in such a way that they will actually eat away at the skin, causing disfiguring, ghastly marks on the body. The ears, nose, and mouth can become disfigured and often times the lips and gums deteriorate in such a way as to make the incisors of the afflicted person more prominent. (1), (5) Porphyria has also been linked to excessive hair growth which may not fit the modern vampire image, but in folklore the vampire and the werewolf represented very similar ideas, and the categorical distinctions have become more refined after the effects of pop-culture specificity. (7) Finally, the idea that garlic is repulsive or harmful to vampires may is a reality for victims of Porphyria—garlic acts as a catalyst for harmful chemical reactions with the incomplete heme molecules, so victims of Porphyria cannot be around it. (5)

It seems highly probable that at some point in the creation of the vampire myth, Porphyria victims influenced the details of the vampire, and grounded people with empirical knowledge of a non-human monster. It is important, however, to realize that other essential ideas about vampires developed separately from the disease and many modern explanations rely on an anachronistic conception of the vampire as well as unfounded speculation. In one of the most popular American Journals, The New York Times, a reporter quoted scientist Dr. Dolphin who says at one point:
that a major treatment today for some porphyrias is an injection of a blood product, heme. Since that treatment did not exist in the Middle Ages, when the myths originated, the victims might have instinctively sought heme by biting human victims and drinking a large amount of their blood, as was supposedly the custom of vampires. (7)

Dolphin later admits that drinking blood would not have helped the afflicted people get a healthy level of heme molecules, but that the victims might have 'instinctively sought heme' as one seeks the answer to a hypothesis. (7)

Most other sources mention that drinking blood could have been falsely considered a helpful remedy, but this information is qualified by inconclusiveness. (5), (1), (3) What is important to note in Dolphin's example is that the vampire legends were in circulation as early as the the 8th century in certain Slavic cultures and perhaps earlier in others. (2) Dolphin's interpretation that victims' instinct would be to drink blood seems to rely on a modern interpretation of the disease as a blood disorder. Even in the past two centuries, when vampire legends were still being taken very seriously, a connection between Porphyria and needing blood or heme material is unfounded and anachronistic. He asserts that 'instinct' is what may have given these victims the insight to drink human blood, however he never gives any reason why a victim would instinctively do something that would in no way alleviate any symptoms except that vampires supposedly did it. Instead of relying on historical or cultural information to understand the practice of drinking blood, he begins to reason circularly trying to carefully match all aspects of the myth to the disease because the idea of a disease is in some way more reliable.

Many other sources are more careful in the way they talk about the Porphyria, (1), (3), (5) and they allow for the fact that the myth could have been influenced by real cases of Porphyria and its specific symptoms, but myth-making is not just the misinterpretation of empirical evidence. To search for the source of a myth is like searching for the source of an ancient religious text—one can make inferences and make strong arguments, but the idea of a source is really a fallacious one. Evidence of the vampire myth exists separately in Chinese history, Eastern and Western European history, Romanian history, and others. (6) Myths developed because it was more difficult to discern valid stories from invalid ones. Validity also had very little to do with experimentation and empiricism as it had to do with socially accepted ideas of religion, culture, and irreconcilability of the uncanny.

Science has a knack for presenting information in such a way as to avoid being wrong, while suggesting many colorful ideas that ignore non-scientific information. The practice of drinking human blood was handled differently in many of the listed scientific articles below, because nothing was scientifically conclusive, but instead of discussing the influence of myth-making culture in order to create a well-rounded multi-dimensional theory, the mainstream scientific papers tended to leave things as scientifically suggestive as possible without making outright erroneous claims. The power of a scientific idea relies on a type of faith as well. And as soon as people invite certain ideas into their hearts, these ideas can come and go as they please, and can take advantage of them, even in the stillness of sleep.

1) The Mississaugua News ,

2) Wikipedia ,

3) Scientific American ,

4) NDDIC ,

5) Daily Cardinal ,

6) Vampires Origins of the Myth ,

7) New York Times ,

Mental Illness and Its Discontent
Name: Keti Shea
Date: 2005-12-08 00:08:34
Link to this Comment: 17345


Biology 103

2005 Second Paper

On Serendip

Keti Shea
Bio 103
Prof. Grobstein

"I'm interested in how society shapes the way we understand how I become eggplant - not just the cultural implications of biology - and in examining how useful biological methods are in other disciplines." (1).

Earlier in this course, we discussed ways in which understandings of biology and scientific knowledge fits into the context of greater social and cultural concerns. As demonstrated by Norma's comment and the comments of others made in the online forum, certain members of the class expressed uncertainty concerning to the extent to which scientific knowledge/ the study of biology is compatible with an understanding of these larger socio-cultural processes (1). In the presentation of studies and compilations of research done on bipolar disorder, I intend to demonstrate the ways in which scientific cannot be separated from cultural systems of value through which this knowledge is produced.

Before discussing these greater issues, an overview and description of bipolar disorder is needed. This disease, which afflicts over 2 million American adults, is characterized by episodes of mania and depression which can last a few hours (rapid cycling) or up to a few weeks (10). Usually developing in the teenage years or early adulthood, symptoms of a manic episode include: increased energy and activity; excessively good mood, euphoria; racing thoughts and fast talking; change in sleep patterns; poor judgment; aggressive or "provocative" behavior; substance abuse; unrealistic beliefs in one's abilities; distractibility (10). There are certain symptoms such as psychosis (hallucinations and delusions) which may occur in both types of episodes.

While these symptoms may appear to be extreme and therefore easily recognizable, complicating factors may arise when diagnosis and treatment are sought. For example, treatment of bipolar disorder is often confounded by substance abuse. This may exist in the patient's history prior to development of bipolar disorder or may have become a form of self-medication in those patients whose symptoms have already appeared (8). The result, as the Mayo Clinic points out, is that "when bipolar disorder and alcoholism occur together, each can worsen the symptoms and severity of the other" (8). That said, no single cause can be attributed to development of bipolar disorder; a history of drug and alcohol abuse is only one factor in a list which includes one's ability to manage stress, genetics, and brain chemistry (5). So what exactly is going on biologically to lead to these symptoms? Studies funded in part by the National Institute of Health have shown a link between overactivity of the protein kinase C (PKC) in bipolar patients (9). The U.S. Department of Health and Human Services additionally reports animal studies which have shown that increased levels of stress impairs cognitive abilities and leads to PKC activation. In turn, this activation of the protein was found to result in "a reduction in memory-related cell firing," a process which allows cells to hold information (9). Further studies have been conducted reinforcing the supposed link between stress and PKC activation, targeting the messenger chemical norepinephrine. When exposed to stress, norepinephrine binds to receptors on cell membranes in the prefrontal cortex, thereby activating PKC (9). Once activated, a series of events occurs in which PKC enters the cell's nucleus and turns on genes (9).

These and additional studies indicate the "biological origins" of a mental illness
which, as Kay Jamison describes, feels "psychological in the experience of it." It is perhaps due to this seeming incongruity (between unseen biology causes and felt psychological experiences) which contributes to the misconceptions surrounding bipolar disorder. One such example of public misconceptions manifests itself in a recent survey directed by Harris Interactive and sponsored by the National Mental Health Association. The survey questioned 1,051 American adults in order to "assess the public's awareness, attitudes and perceptions of bipolar disorder..." (2). The findings indicated that 75% of respondents admitted that their understanding of bipolar disorder came from the media (2). Furthermore, those in the 18-24 age group expressed the belief more than other age groups that bipolar sufferers use the disease as "an excuse for the way they act" (2). Finally, while 60% were able to identify bipolar disorder as a mental illness, only 1/3 indicated that they had any knowledge of the illness (2). In short, the survey and its findings suggest that the media plays a significant role not simply in informing the public about bipolar disorder but in stigmatizing the illness as respondents report that media portrayals are more often negative than positive (2). The degree to which cultural processes influence the public imagination is a topic which demands greater attention but which has no place in this essay. What is important to note however is that biological knowledge does not develop in a cultural void but is shaped by a society's systems of values and codes of meaning.

Furthermore, one could argue that cultural/social forces (such as the media) not only shape public opinion but additionally influence the diagnosis and treatment of bipolar patients. For example a study published in the Journal of the American Medical Association found that 9.8% of primary care patients seeking treatment at a general clinic tested positive for a history of bipolar disorder (3). The study group consisted of 1,157 patients aged 18-70 who were receiving care at a medical clinic located in a low-income, urban neighborhood (3). The results of this study found that 72.3% of patients screened positive for bipolar disorder and sought treatment while only 8.4% of these received a diagnosis of bipolar disorder once treatment was sought (3). Similarly, 49% of those who screened positive reported to have had either a major episode or mood or substance disorder. Despite the fact that evidence of this data was recorded by the primary care physicians of the clinic, they "did not record a bipolar diagnosis either in administrative billing or in the medical record of any of these patients" (3). Finally, the study concludes that the prevalence of bipolar disorder in the urban clinic is related to the socioeconomic status of the population of patients, 90% of which had a household income below $18,000 a year (3). What the study does not explicitly address, however, is the question of race. While the prevalence of bipolar disorder is not biologically linked to age, sex or race/ethnicity, the National Mental Health Association reports that African Americans are less likely to be diagnosed with bipolar disorder and consequently less likely to receive proper treatment (7).

This statement is reiterated and developed further by mental health physicians and psychiatrists. Reports published by the NMHA conclude that severe mental illnesses as a whole are not widely treated (9). Several factors which are implicated include: inability of therapists to agree on a diagnosis, unwillingness of patients to admit to having a problem and poor record-keeping which can complicate patient response to treatment (7). As the previous study seemed to suggest, it is a large percentage of patients who are not receiving treatment. In fact, nearly 2/3 of all sufferers of mental illnesses do not receive treatment, a significant portion given that "suicide is the rule and not the exception" in the case of bipolar disorder (10). While these percentages do not deal specifically with bipolar disorder but with severe mental illnesses in general, the information is still relevant in that it implicates a greater problem: namely, the disparity between scientific knowledge and practice. While knowledge of mental illnesses such as bipolar disorder is incomplete, it is extensive nevertheless, meaning that proper treatment should be provided for those in need of it.

A new question which then arises in this analysis is how is scientific knowledge put into practice? This is an issue which exists not simply at the local level but globally as well, as is suggested by the World Health Organization and World Bank's report, "The Global Burden of Disease." Their findings show that "the ten leading causes of lost years of healthy life at ages 15-44 were: a) Major depressive disorder, b) alcohol use, c) road traffic accidents, d) schizophrenia, e) self-inflicted injuries, f) bipolar disorder, g) drug use, h) obsessive-compulsive disorders, i) osteoarthritis and j) violence"(2). While this list is meant to demonstrate the debilitating effects of mental illness in diminishing quality of life, the list implicates as well the interconnectedness of mood disorders. It is this interconnectedness which complicates diagnosis and treatment.

Due to the absence of diagnostic laboratory tests which can be conducted to determine a diagnosis, it can be difficult for physicians to diagnose mental illnesses. As was mentioned earlier, bipolar disorder can co-exist alongside other mood disorders. These include mood disorders due to a general medical condition such as multiple sclerosis, hypothyroidism or stroke (9). Another example already mentioned is mood disorders which result from substance abuse (5). Bipolar disorder may be associated with hyperactivity and antisocial behavior, meaning that a bipolar diagnosis must be differentiated from one of attention deficit hyperactivity disorder, antisocial personality disorder and borderline personality disorder (2). Finally, the delusions and psychosis experienced in severe episodes of mania in bipolar patients are similar to psychotic behavior seen in schizophrenia, delusional disorder and schizoaffective disorder (4). What this information points to is that when there is not a standardized diagnostic procedure, proper diagnosis is complicated by the array of symptoms exhibited by bipolar sufferers, symptoms which much be differentiated from similar mood disorders in the absence of a standardized procedure.

In conclusion, cultural and social conceptions of mental illness and bipolar disorder in particular contribute to who receives diagnosis and treatment. In this sense, it might be argued that the ways in which culture ascribes meanings and attaches values affect the understanding of biological concerns. To return once again to the course forum area, one student notes that while agreeing with the "...notion that the "bigger" and "smaller" pictures are inextricably connected, for surely they are, I also think there has to be some point where the discussion will lose whatever ground it has in what we as a society have come to call biology" (1). I would assert however that biological knowledge is not produced in a cultural void, outside the influence of social norms. Instead, it is only through the culture of a given society that knowledge, even scientific knowledge, is produced. Furthermore, I would argue that the disparities between knowledge and practice demonstrated by the low treatment rate of bipolar sufferers need to be addressed. This suggests that greater concerns remain not only in scientific knowledge-production but in their actual practice as well.

WWW Sources:
1Biology 103 forum area, on the Serendip web site.

2National Mental Health Association.

3)American Medical Association medical library.

4) Depression and Bipolar Support Alliance.

5)National Institute of Mental Health.

6)Psychiatric News.

7) National Mental Health Association.

8)Bipolar disorder and alcoholism.

9)National Institutes of Health News.

10)Bipolar Disorder: Rapid Cycling and its Treatment.

Date: 2007-09-28 22:41:52
Link to this Comment: 21955

Very interesting. Thanks for the incite.

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