Ron’s diet lacks niacin. He hasn’t developed pellagra, because he consumes a high-protein diet that contains plenty of niacin. Multiple Choice
A beta-carotene
B alpha-tocopherol
C tryptophan
D alanine
The correct answer and explanation is:
The correct answer is C) tryptophan.
Explanation:
Niacin (vitamin B3) is essential for the body, and it plays a critical role in cellular metabolism, particularly in energy production. Pellagra is a condition caused by niacin deficiency, characterized by symptoms like diarrhea, dermatitis, and dementia. However, the body can synthesize niacin from tryptophan, an amino acid that is found in many high-protein foods.
In Ron’s case, although his diet may lack niacin directly, his high-protein intake provides sufficient tryptophan. This amino acid can be converted into niacin in the body, preventing the development of pellagra. The body is capable of synthesizing a certain amount of niacin from tryptophan, and when dietary niacin intake is low, tryptophan can make up for the deficiency to some extent.
Now, let’s consider the other options:
- A) Beta-carotene: This is a precursor to vitamin A, not related to niacin synthesis. Beta-carotene is primarily involved in vision and immune function.
- B) Alpha-tocopherol: This is a form of vitamin E, which is an antioxidant and not involved in niacin production.
- D) Alanine: This is another amino acid, but it is not directly involved in the conversion to niacin.
Thus, tryptophan is the correct answer because it is the amino acid from which the body can synthesize niacin, preventing deficiencies even if niacin is not directly consumed in the diet.