Nucleic acids are polymers of individual nucleotide monomers. Each nucleotide is composed of three parts: a 5-carbon sugar, a phosphate group, and a nitrogenous base. Only two 5-carbon sugars are found in nature: ribose and deoxyribose. 5-carbon sugar (ribose or deoxyribose) forms the central molecule in a nucleotide. By convention, the carbon atoms in the sugar are numbered from the original carbonyl position on the chain using a number plus the prime symbol (â).
Photosynthesis is the process by which green plants and certain other organisms transform light energy into chemical energy. Photosynthesis in green plants harnesses the energy of sunlight to convert carbon dioxide, water, and minerals into organic compounds and gaseous oxygen.
The ultimate source of energy for photosynthesis is sunlight. Plants convert the light energy into chemical energy in the form of glucose, which they can then use as a source of energy in their cells. Energy is released from glucose by respiration.