What is the Significance of Photosynthesis?

i. Helps in conversion of solar energy into organic matter.

ii. Consumes atmospheric carbon dioxide and yields carbohydrates and molecular oxygen.

iii. Evolves molecular oxygen for use by other living organisms and maintains the level of atmospheric oxygen which is continuously consumed by plants and animals during respiration.

iv. Produces carbohydrates and used by plants and animals to synthesize organic acids, proteins, fats, nucleic acids, pigments, hormones, vitamins, alkaloids and other metabolites

Chemosynthesis:

Such reactions in which reduction of carbon dioxide to carbohydrates does not require light and takes place in presence of energy obtained from oxidations of inorganic substances is called chemosynthesis e.g., Nitrifying bacteria (Nitrosomonas, Nitrosococcus) obtain energy by oxidising ammonia to nitrites), sulphur bacteria (e.g., Beggiatoa convert H,S to sulphur), Carbon monooxide bacteria (e.g., Carboxydomonas convert CO to CO₂), methane bacteria (e.g., Methanococcus oxidise methane into CO₂ and HzO) etc.