Two major biological processes in the carbon cycle are
and

Explanation:

Photosynthesis by land plants, bacteria, and algae converts carbon dioxide or bicarbonate into organic molecules. Organic molecules made by photosynthesizers are passed through food chains, and cellular respiration converts the organic carbon back into carbon dioxide gas.

the three components of a nucleotide are the nitrogenous base, the phosphate group and the five-carbon sugar.