The carbon, oxygen, hydrogen and nitrogen are the key elements in aminoacids as all aminoacids contain amine (NH2) and carboxyl (COOH) as functional groups and R group for every specific aminoacid.
Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. Chloroplasts absorb sunlight and use it in conjunction with water and carbon dioxide gas to produce food for the plant.