Botany MCQs for NEET — Practice Questions with Answers

Solarisation refers to the destruction of chlorophyll. This process occurs when plants are exposed to excessive light, which can break down chlorophyll and diminish the plant's ability to perform photosynthesis effectively. This is a protective mechanism to prevent damage to the plant cells.

The light reaction of photosynthesis results in the formation of O₂, NADPH + H⁺, and ATP. These are the key products of the light-dependent reactions, which take place in the thylakoid membranes of the chloroplasts. Oxygen is produced as a byproduct of water splitting, while NADPH and ATP are generated as energy carriers for the Calvin cycle.

In the Calvin cycle, fructose 1,6-bisphosphate undergoes dephosphorylation to produce glyceraldehyde-3-phosphate (G3P). This step is crucial for the synthesis of glucose and other carbohydrates.

Solarization refers to the damage caused to chlorophyll and cell contents due to excessive light intensity, leading to photo-oxidation. This process can impair photosynthesis and affect plant health.

The Calvin cycle, also known as the light-independent reactions or dark reactions, requires CO₂, ATP, and NADPH₂. These components are essential for the synthesis of glucose from carbon dioxide and water.

In the Calvin cycle, the assimilatory power (ATP and NADPH) is used during the conversion of 3-phosphoglycerate (PGA) to glyceraldehyde-3-phosphate (PGAL). This step is crucial for the synthesis of carbohydrates in plants.

The loculus is the internal space or lumen of the thylakoid structure in chloroplasts. Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria, the site of the light-dependent reactions of photosynthesis.

The Calvin cycle, also known as the C3 cycle, involves reductive carboxylation. In this cycle, carbon dioxide is added to a 5-carbon sugar (ribulose bisphosphate, RuBP) and then reduced to form glucose.