The antibiotic penicillin is obtained from: MCQ with Answer and Explanation

Explanation:
Vitamin C is a cofactor for prolyl and lysyl hydroxylases, enzymes essential for collagen cross-linking and stability. Deficiency impairs wound healing and causes scurvy. Vitamin A is for epithelial integrity.

Explanation:
Hexokinase phosphorylates glucose to glucose-6-phosphate using ATP, the first step of glycolysis. Phosphofructokinase is the third step, pyruvate kinase the last, glucose-6-phosphatase reverses the reaction in gluconeogenesis.

Explanation:
Green plants (producers) always occupy the first trophic level in a food chain. Energy flow is unidirectional, moving from the sun to producers and then to consumers, never returning to the sun. Due to the 10% law of energy transfer, the pyramid of energy is always upright and can never be inverted. Thus, statements 1 and 2 are correct.