Why is growth essential for life?

I was writing a paper for my English class in which I had to define the criteria for “aliveness”. In the midst of my research, I came accross a definition for life, which included, amongst other things, growth. My question is, when certain bacteria and viruses reproduce, a fully functional, “full-grown” copy is produced. I don’t think they do much growing, do they? Is growth really essential for all forms of life? If not, perhaps this should be taken out of the definition.

Well, they’d have to, wouldn’t they? Each division produces two daughter cells with half the mass of the original. This would quickly approach the ridiculous if the daughter cells didn’t grow following mitosis.

Yep, all living things need to grow, and for pretty much the reason QED gave. The need to reproduce, and for mechanical reasons the offspring need to be smaller than the parent at the time they are produced. Obviously you can’t produce an offspring and apparent that are both the same mass as the parent prior to reproduction. The mass needs to be made up somewhere, and that requires growth.

Sexually reproducing organisms produce offspring that are notably smaller than the parent and these then have to grow even if the parent does not. Some asexual organisms produce two ‘offspring’ of intermediate size that both have to grow in order to reproduce themselves. But no matter what you do reproduction always requires an increase in mass.

Ok, that makes sense, but now I have another question.

Is there a difference between ‘aliveness’ and ‘life’? That is, can something that does not meet the criteria for life still be alive?

The definition for ‘aliveness’ that I read gives one case which is:
Full of activity or animation; lively

Therefore, under this definition, anamatronic creatures such as those at Disney World could be considered ‘alive,’ but they certainly aren’t living creatures.

If, in fact, there is a difference between something being alive and something living, then I can finally write a conclusion on this stupid paper.

I don’t think you can separate the two things like that. Something which is alive is a form of life, and vice-versa. Which is not to say the definition of life is anything like clearly delineated. “Life” turns out to be somethign incredibly difficult to define, despite the fact that we are surrounded by it.

I have to admit, I didn’t even realise aliveness was a word.

It just seems to be a synonym for liveliness. In which case something can be very lively but not alive. No problem there. The problem is if you start equivocating. Make sure you aren’t using aliveness in the sense of lively in one place and using it to mean ‘state of being alive’ somewhere else.

But there is no clear distinction between something being alive and something living. One is a property of the other.

BTW I assume you have seen Cecil’ take on all this?
http://www.straightdope.com/classics/a971212.html