Final answer:
Beta-carotene is a precursor for Vitamin A and acts as an antioxidant in the body. It is found in plant-based foods, but not in animal foods, and is converted into active vitamin A in the liver.
Step-by-step explanation:
Among the statements given about Beta-carotene, the true one is that it is a precursor for Vitamin A. Beta-carotene is indeed found in plant-based foods as a type of carotenoid, and in the body, it is converted into active vitamin A. This conversion is mainly carried out in the liver by an enzyme called β-carotene 15, 15'-oxygenase. The presence of alpha-tocopherol (vitamin E) helps in this reaction, although beta-carotene itself is not directly a precursor to Vitamin E.
Furthermore, Beta-carotene acts as an antioxidant, helping to protect cells against the damaging effects of free radicals. The body's use of antioxidants, such as Vitamins C, E, and the provitamin Beta-carotene, helps prevent oxidative degradation of compounds in the body. This is essential for maintaining cellular health and defending against environmental stressors.
However, beta-carotene is not found in animal foods, which distinguishes it from Vitamins A and E. Those vitamins are found in both plant and animal sources. Also, to clarify, beta-carotene is a precursor to Vitamin A, not Vitamin E (which is a separate nutrient that also serves as an antioxidant).