CALVIN CYCLE:- Plants prepare food through Calvin cycle using energy synthesized during light reaction. Oxygen released during photosynthesis is released into the atmosphere through stomata present on the leaves while the ATP and NADPH molecules are used in the synthesis of carbohydrate from carbon dioxide and water. Dark reaction, takes place both in light and dark until the products of light reaction, ATP and NADPH, are exhausted. Melvin Calvin discovered that the first stable product 3-Phosphoglycerate. However, only some plants showed 3-Phosphoglycerate as the first product of carbon fixation while others showed the formation of a four-carbon organic acid, oxaloacetic acid. Plants that showed 3-Phosphoglycerate as the first product of carbon fixation were called C 3 plants, and the pathway was called the C 3 pathway. Plants that showed oxaloacetic acid as the first product of carbon fixation were called C