ATI Nutrition Proctored Exam

Correct Answer: C

Rationale: The correct answer is Vitamin D. Although vitamin D, also known as calciferol, has been called a vitamin, it is more appropriately classified as a hormone. Like hormones, vitamin D acts to control the function of other cell types. For example, it helps the body absorb and regulate skeletal calcium and phosphorus levels. Choice A (Vitamin A) plays a crucial role in vision and immune function. Choice B (Vitamin B) is a complex of different vitamins that play various roles in the body. Choice D (Vitamin C) is important for collagen production and acts as an antioxidant.

Correct Answer: B

Rationale: The correct answer is B. Magnesium plays an important role in maintaining calcium homeostasis and preventing skeletal abnormalities. It is involved in more than 300 enzymatic reactions, including energy metabolism, insulin activity, and glucose use. Magnesium is vital to the structural integrity of heart muscle and other muscles and nerves. While magnesium does play a role in blood clotting, nerve impulses, muscle contraction, relaxation, ATP energy release, and metabolism of fats, carbohydrates, proteins, the primary physiologic role of magnesium in the body is related to calcium homeostasis and maintaining the structural integrity of the heart muscle. Choice A is incorrect because it includes functions of magnesium, but they are not its primary physiologic role. Choice C is incorrect as magnesium has several known metabolic functions. Choice D is incorrect because although magnesium is involved in ATP energy release and metabolism, its primary role is related to calcium homeostasis and structural integrity of muscle.

Correct Answer: C

Rationale: The correct answer is C: Secondary deficiency. A nutritional deficiency resulting from decreased intake is called a primary deficiency. On the other hand, a secondary deficiency refers to a vitamin deficiency caused by inadequate absorption or use, increased requirements, excretion, or destruction. Choice A, 'Unmeasurable,' is incorrect as it does not describe a type of nutritional deficiency. Choice B, 'Primary deficiency,' is incorrect as it refers to a deficiency caused by decreased intake, not inadequate absorption. Choice D, 'Codependent,' is incorrect as it is unrelated to the context of nutritional deficiencies.

Correct Answer: A

Rationale: Both statements are true. The effect of vitamin A on the growth of soft tissues and bones naturally extends to the teeth and surrounding structures. Enamel hypoplasia, involving defective enamel matrix and incomplete calcification of enamel and dentin, can be due to vitamin A deficiency. The effect of this vitamin upon surrounding bone directly affects spacing patterns of the teeth within the bone and dentition. Choice A is correct because both statements accurately describe the influence of vitamin A on tooth development. Choices B, C, and D are incorrect as they do not reflect the accuracy of the statements provided.

Correct Answer: A

Rationale: The correct answer is A, Hematopoiesis. Vitamin D plays a crucial role in regulating serum calcium levels, which is essential for maintaining cardiac and neuromuscular function. Additionally, vitamin D is involved in modulating immune responses. However, hematopoiesis, the formation of red blood cells, is not a direct physiologic role of vitamin D. Therefore, hematopoiesis is the exception among the listed functions of vitamin D.