Which of the following functions is true of vitamins in general?
A They are considered macronutrients.
B All yield energy.
C Structurally, they are linked together.
D They help enzymes participate in the release of energy from carbohydrates, proteins, and fats.
The correct answer and explanation is :
Correct Answer: D. They help enzymes participate in the release of energy from carbohydrates, proteins, and fats.
Explanation:
Vitamins are organic compounds that are essential in small amounts for normal body functioning. While they do not directly provide energy like carbohydrates, fats, and proteins, they play critical roles in energy metabolism. The correct statement, option D, highlights this by stating that vitamins help enzymes in the release of energy from the macronutrients we consume.
Vitamins often act as coenzymes, which means they bind to enzymes and assist in catalyzing biochemical reactions. For example:
- B vitamins such as B1 (thiamin), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), and B12 (cobalamin) are heavily involved in energy metabolism. They help convert carbohydrates into glucose, metabolize fats and proteins, and support the function of the nervous system.
- Niacin (vitamin B3) is a component of NAD (nicotinamide adenine dinucleotide), a coenzyme critical in metabolic pathways like glycolysis and the citric acid cycle.
- Riboflavin (vitamin B2) is part of FAD (flavin adenine dinucleotide), another coenzyme that plays a key role in redox reactions in metabolism.
The other answer choices are incorrect for the following reasons:
- A: Vitamins are not macronutrients. Macronutrients are required in large amounts (carbohydrates, proteins, fats), while vitamins are micronutrients, needed in small amounts.
- B: Not all vitamins yield energy. In fact, no vitamins yield energy directly. They assist in the process but are not energy sources themselves.
- C: Vitamins are not structurally linked together. Unlike carbohydrates or proteins, vitamins are individual molecules with diverse structures and functions.
Therefore, vitamins are crucial in supporting enzymes during metabolic processes, ensuring the body can properly use energy from food.