Easy. Because the tilt of the earth, and because the of the distance the earth is from the sun, either more light hits the earth, or less light hits it. This becomes the basis for winter and summer solstices. This also becomes the reason why the seasons change (as the ecosystem begins to accommodate to the changes in energy disposition)
It is thought to partition transcription and processing of messenger RNAs (mRNAs), which occur in the nucleus, from protein synthesis (translation), which is observed in the cytoplasm. Several recent reports have challenged this widely accepted idea by asserting that translation can also occur in the nucleus.
Plants uses carbon dioxide during photosynthesis. Then plants use carbon to make carbohydrates and cellulose. Which animals then respire and release carbon dioxide into the atmosphere.
The largest is the Biosphere
