Name: Joelle Webb
Subject: Complex Molecules
Date: 2001-10-22 13:08:28
Message Id: 494
The topics of discussion in our class are becoming increasingly detailed. Now, we are in the process of describing complex proteins and the structures of our own life forms: DNA and RNA. Even this would require more detail, i would appreciate it if we discussed the physical aspects of how all of these items actually work together. Otherwise a complex protein does not really relate that much to my life.
Name: Debbie Wang
Subject: DNA Replications
Date: 2001-10-26 03:33:43
Message Id: 538
Being that I used to think that I wanted to be a geneticist in high school, I like many have found these past classes on DNA & RNA fascinating. Having a better understanding of DNA replication, it makes me think about the whole cloning phenomenon going on with Dollie the cloned sheep and the ethical/political controversies surrounding human cloning...and in thinking about human cloning, it leads me to wonder about the parts-of-me-in-a-bag example and about how this affects (or doesn't affect) our ideas on the improbable assembly (solely biologically speaking) of ourselves.
Name: Charlotte Ford
Subject: nature vs. nurture
Date: 2001-10-28 22:05:07
Message Id: 539
I was fascinated by the link in our lecture notes to low cholesterol levels' correlation with violent behavior, and by a classmate's suggestion that this could help explain violent behavior in "developing" nations. It's never as simple as nature or nurture; they both inform each other--but how much control do we have over our actions/reactions? To what extent do our genes/diet/chemical reactions determine our behavior? From a biological standpont, where does free will enter the picture? Can free will be explained bio-chemically?
Name: Jessica Blucher
Date: 2001-10-29 10:19:40
Message Id: 541
I found the "cholesterol's effect on violent behavior discussion" interesting, but rather disturbing. I wish I knew more about it. For example, are we talking about HDL, LDL, or both? I know there's more to it than we can cover in class if we want to stay on track. That's the one thing I hate about this class! We find such interesting stuff along the way, but most of it we can't investigate in-depth because it's not the focus of the course. Ah well, it's still fun to learn.
Name: samantha carney
Date: 2001-10-29 10:42:39
Message Id: 542
I also find it interesting and enlightening that all earthly objects are made of the same matter. In fact, I think that this is such an important idea that it should get more publicity! If everyone were aware of all of our similarities and commonalities, perhaps the history of mankind would be different. The future still can be different if we use science to promote these good ideas. There are little discoveries by science every day that abolish stereotypes that we have lived with for centuries (for example that race determines personality traits). If these discoveries got as much publicity as, say, the newest John Travolta movie, would society be different?
Name: Sarah Sterling
Subject: Just a thought...
Date: 2001-10-29 13:00:36
Message Id: 543
As far as diffusion is concerned... do people diffuse in the same way? Will we all eventually become equally spaced throughout the planet (give or take the areas of water)? How strange will it be when highly populated areas have the same number of people as once unpopulated areas. Eventually we (and our waste) will take over the world until it is populated beyond the point where life is able to exist. Which is more likely: That the sun will "burn out" or that we will in one way or another create our own extinction?
Date: 2001-10-29 19:43:03
Message Id: 544
I was thinking about the same thing as Sarah - diffusion of people. In the context of incidents such as the events on Sept. 11, I think this diffusion of the American population would be conciderably more probable. With the advances made, and continuing to be made, in technology, there is really little reason for 1000's of people to be in those high-rise office buildings like the World Trade Centers. You could be white-water rafting in Idaho and send your work electronically to the city. I think, then, that it's possible for the distribution of our nation's population to take on a more diffused or uniform appearance. I wonder if historic migration patterns illustrate this? ...or if the collective community tendency of humans/animals inhibits diffusion.
Date: 2001-10-30 21:49:25
Message Id: 545
we know that the human population is growing at an increasing rate.(exponentially?) this increase is then adding to the number of highly ordered cells or organized systems in our universe thereby, to some extent, decreasing entropy. At the same time an increasing population also spells an increase in conversions of usable energy to heat released into the universe. clearly, for the second law of thermodynamics to hold, more of the second is occurring than the first. what i find intriguing or think should be considered is the rate at which entropy is increasing. can the rate be quantified? what kind of impact do increasingly organized systems have on the rate at which the entropy or disorder of their surroundings increases? could disorder be increasing alongside our population at a faster and faster rate?
Name: Alexis Baird
Date: 2001-10-31 02:17:01
Message Id: 546
This idea is still kind of rough in my mind so bear with me, but: in class we've talked about patterns of movement: how life seems to be moving towards more and more "improbable" assemblies and how all the energy in the universe is moving towards more "probable" states. All this movement appears to be linear in some way and (to me at least) implies a finite end (either theoretically or in reality). My question is then: can the progression of life, energy, the universe, or even time itself ever be considered cyclic rather than linear?
Date: 2001-10-31 19:16:28
Message Id: 547
In the last few classes we have been learning how all matter,including living systems are in constant random motion and states of fluctuation.In that sense,nothing appears to be stable or fixed,but a continuous flow of breaking up and rebuilding(???) to create improbabilites which in turn create more improbabilties.Does that mean nothing is stable??? If so,why do we humans crave so much to cling to things(living and non lving) and desire permanence and stability?
Subject: probability and complexity
Date: 2001-11-02 18:33:59
Message Id: 549
I'm having trouble understanding the concept of "probability" as we're using it in relation to the Second Law of Thermodynamics. On one hand, if we think of an event's probability as the likelihood that it will happen (in the future), it seems pretty much tautological to phrase the Second Law as "the overall direction of change in the universe is always from a less probable to a more probable state." That doesn't really say anything unless we make clear what the more probable state is. As I understand it, the least probable state is the one in which energy is most concentrated. But is concentration of energy the same as complexity? What is the relationship of complexity to energy, probability and the Second Law?
One diagram we saw shows energy coming "downhill" from the sun and then powering a series of transactions, each of which must be result in a state less improbable than the form of energy that powered it. The sun, at the top of the energy hill, represents the least probable state affairs. The sun is clearly less probable than the entire sum of life on earth in terms of the total amount of energy concentrated in each. But structurally, it is significantly less complex. Didn't we say it's made up of nothing but a whole bunch of hydrogen and helium atoms, the simplest atoms on the chart? And we know that there are billions and billions of stars, but we don't have any way of knowing how many planets support life. So how can we make any statements about how probable life is?
Name: Paul Grobstein
Subject: molecules ... and beyond
Date: 2001-11-04 10:08:12
Message Id: 551
Claudia has her finger on a key question not only to her (and to me) but to lots of active inquiries (cf Complexity, Complex Systems, and Chaos Theory ... Complexity and Artificial Life ... Measures of Complexity): what IS "complexity/organization"?
Yes, the sun is "simple" (not "complex") in some important ways but is also, as Claudia says, "highly improbable", so clearly "complexity/organization" is not the same thing as "improbability". The second law says that the universe as a whole moves from less probable to more probable states (both the dissipation of energy from the sun and catabolic processes in biological systems reflect this), and this is a reasonably well defined idea (akin to our mixing parts in a bag, pouring them out, and seeing how many times the resultant does or doesn't display a particular property, such as "being alive"). And that does seem to mean that, over very extended times, all parts would be found in "random" relationships to one another, ie in disorganized/non-complex configurations.
The key point (at least for us) is that, along the way, there can be and are "eddies", places where the movement towards probable states itself creates improbable states (ourselves and, in general, the anabolic part of living systems). These are not only "improbable" (in reasonably well-defined ways, see above) but ALSO "complex/organized". The difficult and unresolved issue is ... what exactly do we MEAN by THAT? The sun and we are both "improbable" in reasonably well-defined ways, but the two also quite different in (at least to us) important ways. The formal characterization of that difference is important (since, among other things, it bears on whether life is "improbable" in a different sense ... whether it will be found elsewhere in the universe) but remains to be satisfyingly achieved.
Happy to have others take a crack at this in the forum this week. Alternatively (perhaps more manageably), here's a different question to get you thinking (if you need one; as always you're free to write about whatever is on your mind):
We've spent the last little while looking at molecules, macromolecules, and chemical reactions, and are about to move on to cells. How has your conception of life been affected by our discussions of things at the level of organization of atoms and molecules? What aspects of life has it helped to make sense of? What aspects of life has it not helped with? What things does it now appear need to be accounted for at higher levels of organization?
Subject: bringing it all together
Date: 2001-11-04 13:49:27
Message Id: 552
We've investigated all of these ideas about atoms up to macromolecules, and we've seen how everything is connected-- such as how the decomposition of energy contributes to the making of glucose and the necessity of the decomposition of glucose to create ATP (which happens to be made of a phosphates, a sugar, and a nucleotide) which in turns is necessary to fuel other chemical reation in a living system.
However, we've still have so far to go until it all makes sense. Even with all of this new understanding, I still can't necessarily find where life comes in--at what point do all of these reactions combine to make a LIVING cell. How do these cells interact to make up a person? How are emotions, ideas, and personality accounted for with these chemical reactions? Any ideas?
Subject: chemical personality
Date: 2001-11-04 15:45:35
Message Id: 553
Sometimes I find that when thinking about cells and macromolecules it is easy to break it down into very small components such as cell organs down to plain molecules and atoms. When considering an organism, it is easy to think of it merely in terms of organ systems interdependent to create the organism. For me, the difficulty lies in trying to retrieve concepts such as emotion, personality, and/or unique thinking from organ systems. I'm sure that we are starting to explain (or already have???)how one gets from neurons firing to modern art, but I'm not sure if I understand it. It seems to be a rather touchy subject; the idea that one's thoughts, feelings, and unique mental traits could be considered to be just chemical reactions.
Name: Rebecca Roth
Date: 2001-11-04 19:30:33
Message Id: 555
Human behavior or differences cannot be explained by biochemical compounds alone. We need to understand why given the same chemical compositions we are still different. Life reproduces with variation. If given the same ingredients, we can even make two completely different foods. There are many combinations--DNA strands.
Name: Charlotte Ford
Subject: creating improbability
Date: 2001-11-05 10:52:20
Message Id: 556
So: systems create order/improbability by transforming the energy expended during the breakdown of improbable systems into probable ones. These transformations occur at both molecular and cultural levels. How are these transformations similar, and how do they differ? Are the chemical reactions that cause molecules to create improbability similar to the chemical reactions that cause humans to build dams?
Also: how is our energy transformed when we die? Where does it go? Obviously we break down--we become more probable--but is it more complex than that? This ties in with the question of what differentiates 'conscious' organisms from 'unconcious' ones. What is that 'conciousness' energy, and how is it transformed?
Date: 2001-11-05 23:35:01
Message Id: 557
I've actually been doing some extracurricular reading lately. It's been a long long while since I've been able to convince myself that such endeavors are necessary, but in doing so this time, I stumbled upon a little piece of prose which seems to fit rather nicely into the flow of this class right now. I find it a stunning, beautiful way of relating science to life in general.
"Molecular docking is a serious challenge for bio-chemists. There are many ways to fit molecules together but only a few juxtapositions that bring them close enough to bond. On a molecular level success may mean discovering what synthetic structure, what chemical, will form a union with, say the protein shape on a tumour cell. If you make this high-risk jigsaw work you may have found a cure for carcinoma. But molecules and the human beings they are a part of exist in a universe of possibility. We touch one another, bond and break, drift away on force-fields we don't understand."
-Jeanette Winterson, Written on the Body
Name: Sarah Sterling
Subject: Space particles
Date: 2001-11-06 16:48:58
Message Id: 568
There are moments during our discussions in which I realize that if it weren't for so many of the things that I never really think about, like atoms and molecules, I wouldn't be alive. All of our talks make me realize how much it takes just to make me work in the way I do. I can't imagine what the unknown particles in this universe are like if these microscopic particles are so significant and so close to us and are very rarely acknowledged in everyday life.
Subject: from life to death
Date: 2001-11-09 02:03:39
Message Id: 583
You often hear how someone died of "natural causes." Why is it that at some point , even if a living organism has functioned and is functioning relatively well, it breaks down to such a probable state that it can no longer function as a living organism? It seems that this mechanism to break down is built into all living systems. Is it just following the way the universe works in terms of the laws of thermodynamics? This whole idea that we start out at a highly improbable state and from then on begin to become more and more probable until we can no longer be distinguished from non living things, is really intruguing when considered next to all of the social and cultural discourses on getting old, aging, dying. Why are we programed to be mortal and where does the left over energy go at the end of the living process?
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