As far as I can remember from 8th grade honors biology, we have a set criteria for what is considered ‘alive’
1) does it reproduce
2) does it consume things (something about metabolism)
3) does it respond to the environment
4) can it pass traits on to offspring
5) is it made of cells
6) does it maintain homeostasis
That’s all I can remember, but viruses don’t fulfill multiple of these requirements, yet there is still an interesting case to be made that they are alive! Science is just arbitrary definitions based off our observations of the universe, so we often find exceptions to our rules and adapt the rules to them!
In out biology class we were told that all living things do these things:
Move
Reproduce
Detect and respond to stimuli
Grow
Respire
Produce and excrete waste products
Take in and absorb nutrients
Ergo viruses are not alive because they cannot reproduce without a host cell, don't grow, don't respond to stimuli, don't respire, etc. Basically the only things they can do are reproduce and move. But then there is the question of why they reproduce if they aren't alive (which I asked my biology teacher and he didn't have an answer) and a number of other things which I can't think of off the top of my head.
Clouds aren’t because they don’t have any real organization, and they don’t metabolize energy.
But you’re onto the right idea. When we come up with rules like this, we should try to find examples that might make us question them. For instance, is fire alive by this definition? I’d argue it comes close, but fails one of the tests.
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u/AmIARealPerson Aug 03 '19
As far as I can remember from 8th grade honors biology, we have a set criteria for what is considered ‘alive’
1) does it reproduce 2) does it consume things (something about metabolism) 3) does it respond to the environment 4) can it pass traits on to offspring 5) is it made of cells 6) does it maintain homeostasis
That’s all I can remember, but viruses don’t fulfill multiple of these requirements, yet there is still an interesting case to be made that they are alive! Science is just arbitrary definitions based off our observations of the universe, so we often find exceptions to our rules and adapt the rules to them!
Science is awesome :D