What requirements are there for life to exist on a planet?

Question

What requirements are there for life to exist on a planet?

Answer 1

beer

Answer 2

H2O

Answer 3

i would think there would need to be water, sunlight, and a sustainable atmosphere for photosynthesis to occur.  plant life will then usually equal animal life.

Answer 4

Well, what we know of so far is water (the biggest one), some form of energy, oxygen.

Answer 5

I think sunlight oxygen and water

Answer 6

a swimming pool

Answer 7

H2O! You must have H2O!

Answer 8

I try to keep away from your questions, because I enjoy them too much and spend far too long thinking up the answers! :)

Anyway, we really don't know too much about the vast universe to know how life - living things - can exist on other planets. It could be silicon based breathing methane, or it could be a creature that swims in a sea of acid, and different gravities would affect cellular structure - if it even has cells. Anything goes, really.

But if you're asking how a carbon based life could exist on a planet, then I think there would have to be an abundant liquid supply of a universal solvent - water being the most likely candidate - stable temperature range (A Sun and a planet orbiting in the "Goldilocks" category), a nice range of stable elements, and an atmosphere that would support the process of biological energy conversion.

(For humans, I think it would be incredibly difficult to find one that would fit us perfectly. We exist in a very narrow range of temperature, pressure, gravity, and need constant supplies of food and water to survive - we just don't know how fragile we are :))

Answer 9

Consider it more like a special space craft. The water is recycled

The CO2 is recycled into oxygen by plants.

Plants keep the C to make there food out of,but that is the fossil fuels recycled.

It is plant fossil not animal fossils.

There are many other cycles that support life here on EARTH.

Answer 10

The only requirement for life to exsist on a planet is water.

Answer 11

We do not know. That would depend upon the type of life.

For life to exist on earth, 12 elements are required. We have prganic life.

Look the 12 and astound your class. not to mention your teacher.