NEET Practice Questions (MCQs) with Answers & Solutions

Violaxanthin is a carotenoid and is known to be a precursor in the biosynthesis of abscisic acid (ABA), which is a plant hormone involved in various plant developmental processes and stress responses.

Phycobilins are pigments found in cyanobacteria and certain algae that contain open-chain tetrapyrrole rings (also known as open pyrrole rings). This structure is different from the closed tetrapyrrole ring found in chlorophylls.

Dimorphic chloroplasts, which refer to the presence of two different types of chloroplasts in the same plant, are present in C4 plants such as Zea mays (maize), Saccharum officinarum (sugarcane), and Sorghum bicolor. These plants use a specialized form of photosynthesis to efficiently fix carbon.

The red pigment in tomatoes is primarily due to a compound called lycopene. Lycopene is a type of carotenoid, which is a natural pigment that is responsible for the red and pink colors in various fruits and vegetables. It is also a powerful antioxidant.

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.