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Bio 103 Week Two: Life? (and science?)

Paul Grobstein's picture

Glad you're here, to share explorations of life. If you're registered in Biology 103, remember to log in before posting here. Others are welcome to contribute without logging in. Such comments though will be checked to avoid spam postings and so be delayed in appearing.

In any case, remember that this isn't a place for polished writing or final words. Its a place for thoughts in progress: questions, ideas you had in class (or afterwords), things you've heard or read or seen that you think others might find interesting. Think of it as a public conversation, a place to put things from your own mind that others might find useful and to find things from others (in our class and elsewhere) that you might find useful. And a place we can always go back to to see what we were thinking before and how our conversations have affected that. Looking forward to seeing where we go, and hoping you are too.

You're free to write about anything that came into your mind this week. But if you need something to get you started, what did you think of our effort to say what life is?  Is it useful?  Are problems doing so relevant to thinking about other things?

Kaitlin Cough's picture

I thought what we said in

I thought what we said in class yesterday, or rather what we cleared up in class yesterday about a fetuses, embryos, and people in vegetative states undoubtedly being alive was fascinating. It got me thinking though. Because while I do agree they are irrefutably alive, I am still pro-choice and I still think that personally, if I were brain-dead, I wouldn't want to stick around waiting for science to come up with something that'll wake me up. But then, am I saying I'm okay with murder? If I think a fetus is alive and yet I am okay with abortion, what does that mean? I think that there are different...stages maybe? of being alive. So a fetus is alive, however...hmm. I've been sitting here for awhile trying to think of something to say to back myself up and I can't. It is a living thing. It has potential. If a mother can't care for it, there's always adoption. Maybe I'm pro-life after all. Maybe not though. Because while I don't think it's ever an option I would consider myself, I find it unfair to tell other women that they couldn't consider it. Their circumstances may be very different from mine. I think perhaps it needs to be taken on a case-by-case basis.
As does, I believe, being in a vegetative state. No one really ever decides beforehand whether or not theyd want to be taken off the machines, but since you can't really decide after...If someone had to choose for you, I think it would have to be based on the individual's circumstances. How long have they been brain-dead for? Is there any possibility they could become responsive again? But how long would it take? Think about it. What if you were out for years and years, and then woke up and everything had changed except you. That would be awful. I don't know. This seems like an enormously difficult question to speculate on, one that would have to be experienced firsthand. You'd never know what you'd do until you were in that situation.

r.mabe's picture

Our first lab required that

Our first lab required that we look at things that are familiar to us as if they were foreign in order to describe and separate the vegetation we examined into categories. This got me thinking about classification not only in science but in our daily lives. It seems to me that while classification makes things easier, grouping things together, on the basis of like characteristics, into boxes allows humans to more easily study and explore the complex world around them. Yet, simplification is not always a good thing. In class we attempted to find a single or set of characteristics that distinguish living from non-living organisms, yet we found this to be impossible. When humans try to fit everything into an established and understandable box we always seem to run into problems. Yet, humans also seem to need to categorize things in order for our brains to process, think about and understand them. If we try to find clear cut lines we may be over-simplifying but if we don’t' draw any lines at all how can we possibly look at/compare/understand anything? How do we reconcile our tendency to categorize with the inaccuracy of doing so?

vcruz's picture

Life as a process

Last week was kind of counfusing and maybe even annoying at some points. I think it was because the questioning of each new characteristic, concept, category, etc. that we would come up with. We are used to not giving much thought to the question of life and when we face that we just feel like thinking "life is us, that, this, anything that's alive--that's it", instead of trying to define what makes us and/or everything alive. As discussed in class, I don't think that we'll ever come up with a real set of characteristics categories to define what's alive. I rather take life as a process. I do not think that anyone could ever explain the meaning of life or what makes us alive, different people might come up with different answers. In my personal belief, only the creator of life can answer for sure these questions--just as any master has a purpose for what he makes, he can only explain why that was made-- other explanations, for me, are rather taken as stories. And the stages, or forms, or reasons of being alive are just part of the process of the whole purpose of each individual.
andrelle's picture

Again the things that I

Again the things that I have taken to be of absolute certainty are now being put into question.  Like many of my peers if I had been asked what is life a week ago, i would have simply answered that life is anything thats alive and people would have propably taken that as an anawer.  I guess i realized how little we really question, and I don't know if that's a good or bad thing.

But I also wonder the way I use to think of life everyone thought of it the same way and I really didn't have to explain myself when I said that life is something that's a live and if that is the case, then i Wonder if going through all this trouble in trying to truly define necessary.  What Im trying to say exactly is by trying to emcompass all these different characteristics about life when we describe it, are we then not making sense at all. 

asavannah's picture

What is life?

The question, what is life? Is one that I found to be pretty difficult to answer. Before this class, I would have characterized something as being alive by it being able to grow, breath, move, needing energy to live, and needing food. As I looked over this list I realized that not everything that is alive shares these same characteristics. In class we came up with a better list that seems to cover most, if not all, of what describes a living organism. The list states that a living organism must be bounded, energy dependent, having an improbable assembly, semi-homeostatic, semi-autonomous, and reproduces with variation. I feel that this is a better list than what I originally thought defined something as being alive.   

kharmon's picture

Life, in my eyes

Prior to our class discussions, life to me was one of those words that you couldn't define without using the word in the definition. Obviously my life is different than that of a fruit fly who may live to see several hours while comparably, I may flourish for several years. What abouit a tree that spends hundreds of years in the same spot while I spend the duration of my much shorter "life" with the mobility to wander the planet. When class concluded on Friday we had successfully established a definition that encompassed all the different varieties of life, and I was satisfied. But now I wonder whether or not our definition is too broad. Can something be alive but not have life? Are those that are brain dead or vegetative alive? Is an embryo alive (from the moment of conception)? Is there something or someone that we've overlooked?

LaKesha's picture

Life Is....

We can't create an exact definition for what LIFE is. I feel that we can always come close but there are so many different life forms that it is difficult to say that there is one way to describe that something is alive. I really thought that lab was interesting because there were so many different ways that the groups came up with how to decifer the different plants. When we were all asked to say how many different humans were in the class everyone had a different answer. It all depends on how the person observing thinks about it. I think that this is the same with life because everyone has a different opinion on what is considered to be alive. I would have never guessed that it would be this difficult to come up with a definition of LIFE. I know that this class won't give me an exact anser to what life is, but I will have a better understanding.
Kendra's picture

The Definition of Life

The last week of class has really had me thinking. Before this class, I never really grappled with 'What is Life?'. I mean, I know whats alive- human beings, animals, plant life etc- but I never really thought about how to define life. I really liked how we were able to classify life based on certain characteristics as an improbable assembly and being bounded. Seriously, I never realized that living things are actually bounded by skin, fur, scales etc!

I found the lab more difficult once we had to actually find ways of classifying the plant life. Although the lab was fun, it caused me to think in a completely different way than I am used to because I never thought to sit down and actually classify plants.

I know there is no concrete answer as to what is life, but I hope to get  a better understanding of it as we go on in this class. 
MarieSager's picture

I went home this weekend

I went home this weekend and my little brother (who is in 7th grade) was doing his science homework and he asked me, "is a tree alive?" I really couldn't believe that we were both covering the same subject and I was like "what?!" but then he clarified and said "is a tree a living organism?" His assignment was to put the entities in a picture into 2 separate categories- living and non-living organisms. He went on to figure out that a tree went into the living organism list, but it got me thinking- are categories useful? I mean, we used them in our lab and without them I don't think we could have created any meaningful system of classification. But how broad do our categories have to be? Or how narrow? And how much overlap is ok? I don't totally know where I am going with all this, but I think that this week in class, we kind of set categories and we used these categories to define life. Categories or characteristics? Do characteristics make categories? .... I guess it's something more to think about. 

OrganizedKhaos's picture


I found that identifying and classifying life was a more difficult task than I would have ever guessed. Not only is there not any one phrase or word which can sum it up but also in finding a collection of words to describe it there are exceptions.

Describing something as being "alive" may seem simple to do but it really just isn't. The discussion we had about our new way of thinking of the scientific method plays into this discussion because of the "crack". Because people have different views and background their own determining factor of whether something is alive or dead will differ.

Thus the description of life and what needs to be present for something to be alive cannot be simplified into one word or phrase and must be acollection of descriptions that work together and allow for exceptions.

Kee Hyun Kim's picture

Defining life


As I mentioned in my previous post, I have had a long time interest in the issue of abortion. Although it is a very complex political, religious and social issue, I believe the core issue in the whole pro-choice pro-life debate centers around the definition of life.


Although both of my parents and many of our family friends are medical doctors (in Korea, one had to study medicine as an undergraduate to become a doctor, which meant that all my parents friends from college are doctors) Nobody has been able to give me a clear answer in what defines life.


Until Fridays class, I continued to have a vague belief that some standard must exist which will allow us to define living things from non living things. Although I had little knowledge in science and biology, I just had this naive belief that soon, smart scientist will be able to come up with the ultimate yardstick to define life and that will solve the ambiguity among what stage of the fetus is it a life. (Whether it may be the stage of conception to 8 month into the pregnancy)  


Although I am still confused and unclear regarding the definition of life, I am no longer anxious. Now I know that although there may be some characteristics that pertains to a living organism (such as energy dependent, semi autonomous, bounded etc) it is simply not possible to produce a single definition of life.



ekim's picture

on scale.

random thought:

it was interesting how during our first lab in finding all the different types of plants, a majority of the groups chose to classify or group the different plants according to shape and size.

is it inherent in humans to always look to some sort of size/spatial scale when it comes to defining differences? and is the human sense of spatial scale distorted because of subjectivity? is it also distorted because we are all different sizes?

Kee Hyun Kim's picture

interesting post

Like you said, its really interesting to see how dependent humans are on their sight. Although we commonly group other senses such as smell and touch, sight definitely has the strongest impact on us. I think this is both because we place such a strong trust on are sight and also because it is used so often... ( I guess our trust on it could be a result from our everyday use)


With the issue of comparing things to our relative size……  I guess its because we are self centered individuals..


Sharhea's picture


In class this week, we tried to explain what life is. Although I have many questions I think I agree with this way of thinking about life. In primary schools, we are taught that life are classified between animals and plants with different branches within them. Categorizing living things as:

  • bounded (by skin,hair etc),
  • being energy dependent (to move, work, grow, maintain etc),
  • having an improbable assembly,
  • semi-homeostatic,
  • semi-autonomous and
  • reproduces with variation;

allows us to think of the possibility that there may be life elsewhere.

I think this list is an excellent list for us to continue our disscussions in class but it may/can change in the future. The idea that science is not the Truth, allows us to believe that we ourselves are truly scientists. Everywhere we go, the places we travel, our relatives' heritage; allows us to have a broad range of observations to create our own stories.

Ruth Goodlaxson's picture

I'm starting to realize

I'm starting to realize that biology can be very controversial. The debate on where life begins is so heated and has such intense personal, political and moral implications in our society. I think this debate would be a good demonstration of "The Crack" in the loopy story that is science, because it's almost impossible to extricate your own political beliefs and personal experiences when thinking about the implications for the definition of life for abortion. It would be very easy to choose and omit certain facts of the "what is life" list for defense of a pro-choice or pro-life argument.

Also, I really like the idea of life and science as a continuous process, rather than a state of being. I think people would be happier if they understood life as constant change, growth, decay and renewal, rather than the routine they grow accustomed to from day to day. Just a thought...

cmcgowan's picture

Class this week has really

Class this week has really made me think about how often we accept things as real or true without even thinking about it.  I think this is because we live in a world that places so much emphasis on facts and "getting the right answers."  I found it interesting that when we were asked what life is, we initially tried to answer with what we have been taught rather than our own simple observations. 

Our discussion in class on Wednesday reminded me of an experience I had last year.  One night as I was falling asleep, I had a dream that I needed a heart transplant. I suddenly woke up and realized that I did not have the slightest idea how a heart transplant worked. I tried to fall back asleep but I couldn't because my mind was awake and thinking about heart transplants.  I knew that I would not be able to sleep without knowing more about heart transplants so I got out of bed and googled it.  Once I learned more, I wondered how doctors are able to perform an intricate process like that but they are not yet able to bring someone back from the dead. I know that there have been miracles where they have restarted someone's heart after a small amount of time but why can't they straight up bring someone back from the dead. 

I guess the answer to my question relates to what we discussed in class about life as a process. There is not just one thing that a doctor could do to bring someone back from the dead because death, as life, is a process. While it might only take one shot to kill someone, fixing the wound is not enough to bring them back because other parts of the body have already shut down. 

Shanika's picture

"A little understanding of what Life is"


After understanding that life is a process of exlporations, observationsand so on, i guess it does makes sense that their are different states if mind of being a live. There is not just one characteristic of living things but many. But how do we know that some characteristics apllies for all living things. Well we don't. But from other's observations i feel like we came up with a good list in class that makes things alive.

Living things do have boundaries, they are energy deoendant, they are indeed semi-homestatic, they are also semi-atonmous, and they do reproduce with variation.

If somehting can deal with change and overcome obstacles I am convinced that it is alive.

The many observations poeple make about what is a live and what is not, determeines their meaning of life. I still cannot tell you from my observations," what life is?!" But I do undertand their are steps that I have to take befor answering the questions. But how do I begin?


Shanika Bridges-King
LuisanaT's picture

The world is just one big onion

There are just so many layers and things to acknolwedge when investigating life. While thinking about the different disturbances we human beings overcome, I came across simply putting your face in water. During this time your body automatically reacts and forces you to hold your breath. Now this subtle resistance may be misinterpreted for the never-ending struggle to suvive in this world. If so, are there organisms who just live, lacking purpose in life? Are there purpose in life living? This all sounds too familiar to us.

You'd think it'd be easy to classify organisms that have never been documented before. For the lab, the organisms were all from a little patch off the paved road, I can't even begin to think about the entire Galapogos island. It's mindboggoling the amount of detail and consideration you have to put when categorizing the organisms. There's Certainly a lot of responsibility in the hands of a scientist.

PS2007's picture

What is Life?

I thought our discussion of how to classify life in class was very interesting. I had never really thought about this before, so when the question was posed to us in class I thought it would be really easy to answer. After class, I started to think about what seperates humans from other organisms, or even if humans can be seperated. I have heard before that humans have a higher level of consciousness, but how is this measured or defined? How do we know that other animals don't communicate with the same complexity?
Samar Aryani's picture

The Definition of Life

The class discussions that have been held so far have been very interesting in nature, especially the discussion on what defines life.  I realized going into the conversation that there was not going to be a definite answer but at the same time I did not expect the 'answer' to be so complex.  It is amazing how a living thing is made of up of a collection of properties.  For instance, one living object may breath, move, and die, but it can't reproduce.  Also, the idea of a living thing as an improbable assembly seemed to make more sense of the characteristics of a living thing.

Our discussion on Wednesday's class about Langston's ant and whether or not it is alive as well struck me because I still can't decide whether or not it is alive.  After making some conclusions, one that stuck with me was the idea that maybe there isn't a sharp distinction between living and non-living things.  I believe that with the observations made in class in correlation with those of other biologists, one day a more concrete definition of what life is may form. 

Catrina Mueller's picture

I think that the way we

I think that the way we defined life in class is as good as it's going to get. There is no way without ripping apart a being/non-being to tell if it is "alive" or not in one characteristic. Improbable construction is definitely not something that I would have thought of on my own, but it useful to define things that are living. I know that if you ground a rock to dust, it would not be a rock anymore, but it still could become a rock again given many years and some pressure. An animal would decompose into the earth with no chance of changing back into animal. I think that it would be a better system if we could find a way to narrow it down to one characteristic, but that would be fairly impossible, so this classifacation is as good as we can humanly get at the moment.

kgould's picture

so... what about the viruses?

So the whole time that we were discussing "what is life?" in class, my mind kept turning to one topic: viruses.

Because no one can really decide whether or not those little particles are considered "alive." Yeah, they have genetic material (improbable assembly?), yeah, they reproduce (only in a host cell, but reproduce none-the-less), and, to a limited degree, they respond to changes in the environment when inside an infected cell.

But viruses have no cellular composition and they can't metabolise on their own.

If viruses were considered "alive," would that change everyone's view of life? Would other seemingly "non-living" particles, like prions, also be considered candidates for "life?"

I'm just curious about other people's opinions and ideas. Does anyone lean one way or the other?

Jen's picture

In trying to classify life,

In trying to classify life, I was initially frustrated when I was told I could not use cells as a qualifying characteristic of living organisms. Afterall, years of research and hours spent looking at animals and plants under the microscope clearly showed that this is a characteristic of living things. The problem with it is that it is not a directly observable characteristic. Still, it is an accepted truth. Why can't I use it?

Then I realized that when applied to life beyond Earth, this characteristic might not hold true. Suppose life on Planet Farther doesn't even use DNA or similar, Earth-like cell structures. Plants aren't even guaranteed to be green. How would we know that these were plants? A definition of life based on what we observe with the naked human eye gives us the flexibility we need to understand new observations in different settings.
Rachel Tashjian's picture

Problems in defining life.

I was thankful that in class, even after we defined "life," we agreed that doing so still creates a set of problems (e.g., questions about where these things come from, etc). Reading the suggested blog topic for this week,  I was reminded of another definition and the set of problems this thinking creates. Over the summer I was talking with my parents and some of their friends (because adults are awesome too) about art/music.  One of my parents friends is an art historian and owns an art gallery, and he said that he has no idea what else can be done in art because it's all been done. I agreed at the time, and felt similarly about music (which I think came to its "it's all been done" moment John Cage "wrote" "4:33'', which is four minutes and 33 seconds of total silence and yet still considered music. Hilarious).

But today, our discussion in class led me to a new thought. We said that the definition of life should always be changing because of all the questions it creates. Likewise, I think the definitions/genres of art and music should always be open to change. I may see something that I don't think is music (a reexamination of "4:33", perhaps?) or art, but asking questions - where does rhythm come from? what is the definition of an instrument? - might change my mind.

eharnett's picture

Life: What is it?

As I looked at the picture of the desert before class and pondered about what life actually was, I came up with some criteria in my head.  Most importantly, I believed that to be alive the object must do some form of energy transfer, along the lines of photosynthesis or cellular respiration.  I believe that if we used this criteria, we could limit what is alive and what isn't.  When something stops transfering energy, then it dies (the opposite of life).  I also believe that being "alive" would mean something is made up of cells that are constantly interacting with each other. 
ekim's picture

on life.

in class (on monday), we stopped at living things being defined by its "improbable assembly" and as having a "collection of properties." But then how many properties would qualify as being a collection of properties, and therefore a living thing? And if science has no right or wrong answer, does that quantity in defining a collection of properties depend on The Crack?
Kaitlin Cough's picture


I posted this before our discussion in class today, so I guess we've already got a sort of list of ideas about what life is, but I'll leave this up anyway...
What is life?
I think to be "alive" in the sense of the word as we know it, (i.e. things that we say are alive on earth), an entity must satisfy several important qualities. It must:
-take in energy
-grow and develop
-respond, adapt, and evolve over time in response to its environment
-be able to die (then again, we can only define death once we have defined life)
-have the capacity to reproduce and/or aid in reproduction of its species at some point in its life (I'm trying to cover the "males can't actually reproduce so they're not alive/women over 60/etc. questions here)

I also like the idea that living things are ordered-if you grind something up it won't look the same, however, I think that's a bit broad. Because, again, you could say that's true for many, water bottles, etc. Also something that has cells...although I agree we can't observe that from the window of our spaceship, so we'd have to make observations for that in a lab. Those are the few criteria that I think of when I think of a living thing though.

I'd like to talk more about the abortion question though, because I'm unsure at what stage a fetus can do those things, or what things it can do at certain stages. That would help me form an opinion for the "is abortion murder?" question.