AP BIOLOGY

Detailed explanation-1: -(A) Photosynthesis in land plants fixes atmospheric CO2 (inorganic carbon) as organic carbon, which is either stored as plant biomass or in soil, or is decomposed back to CO2 through plant and soil respiration.

Detailed explanation-2: -A crucial step in the Calvin cycle is the fixation step, which takes in carbon dioxide and joins it with an intermediate compound (ribulose bisphosphate), thus incorporating inorganic carbon dioxide into an organic compound. RuBisCO (ribulose bisphosphate carboxylase oxygenase) is the enzyme that catalyzes this step.

Detailed explanation-3: -Photosynthesis is the process that changes carbon dioxide into organic molecules. Plants take in carbon dioxide and water, and they then use sunlight to create the photosynthesis reaction. Photosynthesis converts carbon dioxide and water into glucose (an organic molecule) and produces oxygen as a by-product.

Detailed explanation-4: -During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.