Tuesday, September 8, 2009

Fun Moment in BS148H

Are viruses alive?
In isolation, they are unable to replicate its own genes or regenerate its own supply of ATP.

Now...try substituting "human" for "virus."
And if we really want to push buttons...try substituting "fetus" for "virus."

Not perfect, as we can argue over exactly what is considered "isolation" and that kind of thing. But fun to think about.

6 comments:

Greg said...

Umm...what? Granted I haven't taken developmental biology, but fetuses are responsible for their own cellular reproduction and AFAIK produce their own ATP -- at least, I can't imagine any ATP mechanism that would work since they're sub-cellular particles that every cell has the machinery to handle. Fetuses get plenty of support from their mother, but they definitely aren't unalive in the ways a virus are.
You were talking about this in a *bio* class?!??

Becca Farnum said...

An Honors Bio class, in fact. lol.

The point is not that fetuses can't produce ATP...it is that they cannot without that continual support from mother of nutrients, etc. And humans can't without taking in other cells either.

Charlie said...

I'm with Gregory. Umm... what?

Receiving energy from an outside source is common to all living things.

One argument against viruses as life is that they cannot (given appropriate energy) replicate their genes without assistance from some other organism's gene replication mechanism. If the class simply said "in isolation", I suppose it was speaking loosely, but certainly the need for another cell's replicator was implied.

Everything else generally considered "life" can replicate its genes (when given energy).

Asking whether viruses are alive can be a valuable discussion in a biology class. But the gene argument doesn't transfer to humans, regardless of their current attachment to their mother.

Becca Farnum said...

I'm not against either of you.

On a related and yet not note, separate from Human and Fetus comparison - does Papa think viruses are alive?

Charlie said...

OK, actually I'm not with Gregory. I'm with Scribble (a cute black mutt bunny). Gregory is a couple thousand miles away.

I think "alive" is a concept constructed by humans that is fuzzy around the edges, as are most concepts. I'm not a Platonist when it comes to concepts like "life." I think viruses live (or don't live) on the edge of this concept.

From a biologist's standpoint, I'd say they're "life" because biologists study life (built in to the name, eh?), and viruses are definitely something biologists want to study, and are not a particular part of some other life form. So construct your definition carefully. :-)

Becca Farnum said...

That was the topic of today...how the heck are we defining what we're studying?

But your last point does not stand, Papa. Biologists study life, yes. They also study the environment and surrounding things that impact life. They may study how water impacts life, how rocks impact life, etc. This does not make water and rocks living beings. (Not that I'm saying that they're not...oh, crikes.)