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Bio 103, week 2

Terrible2s's picture

Welcome to the on-line forum for Biology 103.  This is a place for thoughts in progress, a place to leave thoughts and questions that others may find useful and find ones that you might find useful, a place for conversation.  Join in, and let's see what we can make of life together.  If you're registered for the course, be sure to sign in before posting.  Others are welcome to join in as well but posting of comments will be delayed to check for spam.  You're free to write about whatever has struck you.  If you need something to get you started though what do think of the our efforts to define "alive" and "life", of life as process?

achiles's picture

life and living

In reading the previous comments on the distinction between life and living, between living and non-living, it has become very clear that the subjectivity of this debate makes it impossible to reach a consensus. Here is the danger of scientific "fact" or even theory being used to bolster political and ethical opinion. In a debate so touchy as the one on abortion (and on stem cells), each side is using the most convenient "scientific" definition of life and living to argue for what is undoubtedly an ethical and faith-based opinion. Many others in the class have raised the question: what role does faith play in science? I think it provides the purpose for many ground-breaking observations in the history of earth and human sciences. It should not, I would argue, be present in the observations themselves. Faith may spark curiosity, but it shouldn't form a scientist's perspective. You can't prove right and wrong; morality is a social construct. So how can a debate that is rooted in defining the moment that the life of an organism acquires value ever be scientifically resolved?

Serendip Visitor's picture

defining life

After discussing this topic for a little over a minute, my brain started to hurt. I decided to look at the dictionary's opinion and I picked my two favorite modern day definitions:
1. the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction, and the power of adaptation to environment through changes originating internally.
2. the sum of the distinguishing phenomena of organisms, esp. metabolism, growth, reproduction, and adaptation to environment.
I really REALLY like the part about adaptation to environment.

xhan's picture


In class, we established that what we believe is "alive" is determined by how we define life.

Since the word life, initself, is such a broad term, there are various definitions of life, and thus allows for various interpretations of what life ought to be.  Though I recognize that people have different perspectives as to what life is, I believe that there is an over-arching, "standard" definition of life that people use not as a means of labeling or classifying(or just that), but as a means of making sense of the world. I think that we can either focus on differences or on similarities, focusing on similarities allows us to have a better understanding about the world inwhich we live.

Although our definitions, ideas, and beliefs may not be entirely accurate, we constantly revising, refining and seeking ways in which we can expand our current conceptions.

jingber's picture

Meaning of "life"

I think a discussion about what makes up life can easily and needlessly get bogged down in semantics.  Language is an artificial construct, and while it may be initially dismaying to think about in this way, the meaning of any given word is arbitrary.  Fortunately, we've all had many experiences with the word "life", and we agree on what is alive and what is not (at a remarkably high rate given the subjective nature of semantics.)  For the purposes of analyzing what life is, we have to work within the construct of what the generally accepted definition of "life" - the real puzzle being figuring out how to translate the shared ideal of the word to an acceptable written definition.

dchin's picture

Week 2

Perhaps the reason that it is so difficult to pinpoint a definition of what it means to be alive is because this constantly changes as things become more or less significant to us. For example, before the dangers of deforestation were truly in the public eye, people did not consider trees "alive" enough to save from being cut down. However, we now have environmental groups chaining themselves to trees in order to protect and save forests from being destroyed. Because society's view of trees and deforestation has changed, due to the exhaustion of Earth's resources, their significance has changed as well. We give greater life to the things that have a direct impact on us, thereby always assigning and taking away value from our environment as our circumstances change.

Karina G's picture

Life -Week 2

This past week we talked about defining what we see and define as a living organism. I'm sure most of us didn't think it would be that  difficult. However we usually go by what other people say and have already defined for us. That is why it is so hard to question and go through the thinking process to come up with a definition.  Finally we managed to come up with some characteristics that a living entity has.And when I look at them they seem so obvious but it was hard to think of them.  :)


paoli.roman's picture

Reflection on Week 2

 I enjoyed the discussion we had on determining what is life when we analyze it using the word "alive". I am still not completely persuaded by the ideas that have been shared in class since it is such a complicated subject and I am still trying to understand it myself. Yet I continue to question the idea of classification; what terminologies am I using (and how) to distinguish what is alive and what is not. What should I call a living organism and why? This weeks lab was extremely fun and it made me understand how classifying objects can be a "red flag" in science and one should always be careful when doing so. I understand that there should be room for debate and specualtion but something about the topic of life and questioning it makes me feel uneasy. 

dchin's picture

I completely agree that

I completely agree that classification in science is extremely important. As we learned with our lab, the chosen classification system can yield completely different results. With the system that we used, shrubbery and trees were the same type of plant. This subjectivity in science, like you said, "makes me feel uneasy." If someone had presented an argument in favor of putting trees and shrubbery in the same category that was persuasive enough to win over a large number of people, that is the classification we would be using.

cejensen's picture


One thing I wanted to say in class but didn't get a chance to is that one important distinction to make when trying to define life is that between life in general and intelligent life. As we are an example of intelligent life, it is sometimes hard for us to differentiate between the thoughts, feelings, and autonomy (all life has autonomy, but not necessarily to the same degree that many animals have) and life. Things without brains are still classified as alive. Another thing we tend to do, as animals ourselves, is, when thinking of life, to think of the more complex forms of life such as animals and plants. I think we haven't talked enough about things like bacteria and microbes, which also are classified as alive.

I believe this also brings up another interesting point. One thing Professor Grobstein brought up in class is that living organisms are highly complex and have an "improbable assembly." However, some forms are more complex than others, therefore, some forms of life are more probable than others. More complex forms are less probable while less complex forms are more probable (right?). I would assume that the life we would be most likely to find elsewhere would be something like bacteria. So at what point is something complex enough to be called life? Or is that question irrelavent because there are so many other factors to defining life?

ktan's picture

Life...or something like it

I was reading a textbook for another class and came upon what I feel is a very well phrased idea that could be applied to our discussion about life. I've altered the following extract to fit our forum: "if everything that occurs in the world is considered to reflect [life], then the term becomes hopelessly stretched...if everything is [life], why use the term at all?...The opposite danger is to define so narrowly that one neglects features that may be highly influential."
I've fallen in love with this phrase because it's true for a lot of things. We can talk philosophically about how everything is alive-a pencil, the wind, the fibers of thread, whatever-but we cannot (and do not) live in an abstract world. In reality (this term, by the way, can also be applied to the phrase above), humans set the boundaries for the definition of "life" in relation to what makes sense/is conceivable for us.
During the lab, we pretend to have gone to a different planet where we categorize objects in a whole new way. It dawned on me, however, that no matter what we do, or how we try to do it, we cannot escape societal prejudices and biases that have been implemented in the very core of our being. In order to have successfully re-categorized the objects we observed in these unknown planets objectively (and again, the definition for this term has been defined by humans), we would need to have been born in that planet, grown up there, and founded that planet's human(?)ity. I think that since the beginning of human consciousness (or maybe even before?) and throughout its progression, humans have used collective summaries of observations to define life.

sophie b.'s picture

I agree, in that the majority

I agree, in that the majority of things in our world are social constructions, perhaps including life itself. It doesn't mean that the implications felt are not very real. The idea that some races, and genders are subordinate to others is a human fabrication, and yet racism and sexism are very real global issues. Perhaps science itself is nothing more than a coping mechanism, something can help us manage a world that at times can seem incredibly abstract and frightening. So perhaps there is no method of defining life other than the instinctual, we just have to know what it means to be alive the way in the same way that we believe we know what it means to be a man, or what it means to be a woman.

Paul Grobstein's picture

using story telling to get beyond "the instinctual"?

Or maybe, by reflecting on the "instinctual" we can change our "social constructions" so they create fewer problems for us, both now and in the future? 

ED's picture

In response to Terrible2s and JPierre

In response to Terrible2s:


"You can't observe a soul (that I know of)."


In defense of art, creative writing, etc-- yes, you can observe a soul. We just don't know how to observe it empirically. In my opinion, not being able to prove something with definite measurements/numbers doesn't mean that thing doesn't exist. I think spirituality and religion exist for a reason-- I don't think spirituality is just made up. My mother claims that new born babies have clear personalities (which would contradict JPierre's statement that fetuses don't have a life).


This is something from another class I'm in, but it definitely has to do with "the type of science we're doing in this class" vs what I've found to be called "reductionist science" ([T]ruth science).


In The Omnivore's Dilemma, the author (Michael Pollan) talks about a man named Sir Albert Howard (1873 - 1947). He was an English agronomist who formed the philosophical foundations for organic agriculture. He said: "We need to treat the whole problem of health in soil, plant, animal and man as one great subject." Howard did no "hard science" to speak of, only general observation. Yet with that sort of observation, he was able to state confidently that "soil fertility" had a direct impact on "the  national health". 


Then this guy named Baron Justus von Liebig, a German chemist, "set agriculture on its industrial path" by introducing "NPK"-- an acronym for the main chemicals in soil that nourish plants. This forever changed the way we farm. Most/all fertilizers have an "NPK" ratio on them. But here's the catch-- this chemist discovered this, then people took it (and still take it) as the Truth-- as in, people don't question this way of farming at all now. I think it's okay to accept that nitrogen, phosphorus, and potassium are in the soil and help plants grow-- but it's not okay (in fact it's dangerously ignorant) to believe that NPK IS ALL THERE IS TO IT. That is reductionist science.



JPierre's picture

Life vs Alive vs Living

I thought that the debate about life vs living was really interesting. That question really forced me to analyze those words and their meanings. After class, I decided to look up the most common definitions in the dictionary. Merriam Webster defined life as "the sequence of mental and physical experiences that make up an individual", whereas it describes the process of living as "exhibiting the life or motion of nature".

I somewhat agree with these definitions. I believe that to live or the act of being alive simply means to exist. Living signifies molecules, cells or (whatever is needed for that person or thing to function), all working inside to make sure that you as a person or thing function.  Living is a physical aspect, which I feel like everyone or thing can be (of course when I say "thing", I mean examples like plants or animals, not inanimate objects such as paper clips).

However, life is a little more difficult to achieve. life is about experiences, spirituality, emotions, thoughts, and etc. You can live and never experience something such as a life. A flower is living but will never experience the pain about its first breakup or the loss of a friend, or the happiness when receiving a diploma from college. It will never fear a deadline for a 20 page paper that it has never even started. A plant is incapable of experiencing this. And this is the same for a fetus in a mother's womb. Although it is living, it most certainly does not have a life.


JJ's picture

 I agree with JPierre about

 I agree with JPierre about what she said with "molecules, cells...all working inside to make sure that you as a person or thing function". To me, the key word is function- I see living organisms as having several functions (no matter how basic), such as eating through hunting or scavenging, and reproducing, so to perform these functions the living organism needs to have a system of cells that allow it to go through these behaviors. Whether a plant, the simplest little worm, or a more complex animal, these are living because they need to grow, "eat" (absorb some energy source), and reproduce. No living organism has a static life. While it sounds simple, we all knew as little kids that things started out as babies and eventually became "grownups", and this idea is applicable to anything alive. As Professor Grobstein mentioned in class, a tree starts as a seed and grows into something bigger, just as an animal grows up. They need outside resources to help them do so-the energy source- and also an internal system to make them function. When this system ceases to work, the living thing's life cycle is over. I guess you could argue that a rock or nonliving thing (to me) can change, but it has no internal system, no "plan" in its DNA that causes instincts to push it to find an energy source or reproduce, and it must be changed by something external. 

Terrible2s's picture

Facts and Faith

So I was thinking about our debate/different definitions of alive. I was wondering about religion. The religion I was raised with sees abortions as wrong because it says that the soul enters the body at an early stage in the pregnancy. So basically it defines "life" or being "alive" as having a soul. But this is a little wishy-washy for science. In regards to our classroom discussions, we're basing beliefs off of summaries of observations. You can't observe a soul (that I know of). So does religion or spiritual belief have any place in science? I know that seems like a stupid question, but we're looking at science so differently now, I was wondering if the questioning and stories could lead to faith and the unseen. Could a summary of an observation or a stance taken on an issue based off a summary of observations include something having to do with unseen things? It seems so integral to many debates, and yet science, traditionally, doesn't touch it (or at least it is very very controversial to include in a fact-based article). But with no facts, can there be faith?