The food chain starts with: MCQ with Answer and Explanation

Explanation:
Pyridoxal phosphate (PLP), the active form of vitamin B₆, is a coenzyme for transaminases (ALT, AST), decarboxylases, and other enzymes in amino acid metabolism. Thiamine in decarboxylation of keto acids, riboflavin in redox, niacin in NAD/NADP.

Explanation:
Turgor pressure from water in the vacuole pushes the cell membrane against the wall, maintaining rigidity. Plasmolysis occurs in hypertonic solutions; osmosis is water movement; high solute concentration lowers water potential.

Explanation:
Coral reefs grow by accumulation of calcium carbonate skeletons secreted by living coral polyps, but the reef structure itself is non-living. It increases in mass externally (accretion). Mushrooms, mango trees, and bacteria exhibit intrinsic growth by cell division, characteristic of living organisms. Thus, coral reef growth is non-living accumulation.