Nokea
Each statement is true of water-soluble vitamins, except one. Which is it?
- A. Act as coenzymes
- B. Deficiencies develop rapidly
- C. Daily intake is necessary
- D. Absorbed in the jejunum
Correct Answer: B
Rationale: The correct answer is B. Water-soluble vitamins do not develop deficiencies rapidly because the body does not store them for long periods. They must be obtained through food constantly. Choice A is correct because water-soluble vitamins often act as coenzymes in various metabolic reactions. Choice C is correct as daily intake of water-soluble vitamins is necessary since they are not stored in the body. Choice D is incorrect as water-soluble vitamins are absorbed primarily in the small intestine, particularly in the duodenum and ileum, not the jejunum.
You may also like to solve these questions
Each statement is true of rickets, except one. Which is the exception?
- A. Rickets is being diagnosed more frequently in the United States.
- B. Rickets is caused by vitamin C deficiency.
- C. Tachetic deformities such as bow legs or knock-knees develop.
- D. A narrow and distorted chest occurs.
Correct Answer: B
Rationale: Rickets is caused by vitamin D deficiency, not vitamin C deficiency. It usually occurs in children who are 1 to 3 years old. The name rickets came from the word 'wrikken,' meaning 'to bend or twist.' Common manifestations of rickets include tachetic deformities like bow legs or knock-knees, a narrow and distorted chest, and failure of the epiphyses of bones to develop normally, resulting in twisted and warped bones. While the diagnosis of rickets may be increasing in the United States, it is not caused by a lack of vitamin C.
When carbohydrates are eliminated from the diet to lose weight, which nutrients are most likely to become insufficient?
- A. Iron, fiber, and protein
- B. Iron, fiber, and vitamin K
- C. Vitamin A and vitamin C
- D. Iron, fiber, and B vitamins
Correct Answer: D
Rationale: Iron, fiber, and B vitamins are most likely to become insufficient when carbohydrates are eliminated from the diet to lose weight. Carbohydrates are a primary source of B vitamins and fiber in the diet. Iron can also be obtained from plant-based sources like legumes and whole grains, which are often eliminated when carbohydrates are restricted. Choices A, B, and C are incorrect because protein, vitamin K, vitamin A, and vitamin C are not primarily sourced from carbohydrates and are less likely to become insufficient solely due to carbohydrate elimination.
Each is a physiologic role of vitamin D, except one. Which is the exception?
- A. Hematopoiesis
- B. Cardiac and neuromuscular function
- C. Immune responses
- D. Serum calcium regulation
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.
Which physiologic role does vitamin C play in the body?
- A. Transcribing DNA to RNA
- B. Absorption and regulation of calcium
- C. Protects integrity of cellular membranes
- D. Catalyst for synthesis of blood-clotting factors
Correct Answer: C
Rationale: Vitamin C plays a crucial role in protecting the integrity of cellular membranes. It is essential for collagen synthesis, which is important for wound healing and maintaining skin, blood vessels, and other tissues. Choice A is incorrect as the transcription of DNA to RNA is facilitated by vitamin A. Choice B is incorrect as calcium absorption and regulation are functions of vitamin D. Choice D is incorrect as vitamin K serves as a catalyst for the synthesis of blood-clotting factors, not vitamin C.
Scurvy is caused by a deficiency of which vitamin?
- A. Vitamin A
- B. Vitamin D
- C. Vitamin E
- D. Vitamin K
Correct Answer: C
Rationale: Scurvy is caused by a deficiency of vitamin C, not vitamin E. The symptoms of scurvy include spontaneous gingival hemorrhaging, perifollicular petechiae, follicular hyperkeratosis, diarrhea, fatigue, depression, and cessation of bone growth. Vitamin A (Choice A) is important for vision and immune function, Vitamin D (Choice B) is essential for bone health, and Vitamin K (Choice D) is necessary for blood clotting. However, none of these vitamins are associated with scurvy.