Answer: Vitamin B complex.
- A Vitamin A, for vision and skin health
- B Vitamin B complex
- C Vitamin C, for collagen synthesis
- D Vitamin D, for calcium absorption
Correct answer: B. Vitamin B complex
Explanation: B vitamins (thiamine, riboflavin, niacin, etc.) act as coenzymes. For example, NAD+ is derived from niacin (Vitamin B3).
As substrate concentration rises, reaction rate increases steeply at first, then plateaus at Vmax once every enzyme molecule is working at full capacity; Km is the substrate concentration giving half-maximal rate, and a LOWER Km means the enzyme reaches that rate with less substrate (higher affinity).
Concept context
Carbohydrates, proteins, lipids, nucleic acids, and enzyme kinetics. Essential foundation for understanding metabolism.