In a closed ecosystem, what provides oxygen, and nutrients?

Question

the ecosystem has the following in it:

- 4 guppies

- 4 strands of aquatic plants

- 4 snails

Answer 1

in a closed ecosystem the sun sends in light which gives the plant the energy that it needs to carry out photosynthesis which is the process of combining water and carbon dioxide (what animals breathe out) into sugars which then feed the plant and the animals will eat the actual plant itself and retain that energy to use for themselves. these animals and plants will go on to die after creating offspring and their bodies will decompose into nutrients that the plants will absorb from the soil along with water to then create sugars in which the cycle is then restarted

no ecosystem is truly closed because the sun is constantly inputting energy that the plants then use

Answer 2

Snails?

Answer 3

and it works?  The plants would provide the oxygen, the snails would provide the nutrients

Answer 4

Plants create oxygen and nutrients.  The guppies and snails feed off the plants and create co2 that the plants need to breath.

Answer 5

The plants provides the oxygen if it is photosynthesizing. Decomposition of organic matter will release the nutrients into the environment in usable form for the plants. The animals must eat to get their nutrients.

Answer 6

Aquatic plants=oxygen

Answer 7

The plants provide for the ecosystem, and the creatures return the favor