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DHN 101 Exam 3 — 100 Original Practice Questions
Vitamin Basics & Fat-Soluble Vitamins (1–25)
1. Which of the following is an organic micronutrient?
A) Calcium B) Iron C) Vitamin C D) Sodium
Answer: C. Organic compounds contain carbon; vitamins are organic. Minerals are inorganic.
2. Which vitamin is synthesized in the skin upon exposure to sunlight?
A) Vitamin A B) Vitamin D C) Vitamin E D) Vitamin K
Answer: B. UVB rays convert 7-dehydrocholesterol to vitamin D3.
3. A condition associated with vitamin D deficiency in adults characterized by softening of
the bones is:
A) Rickets B) Osteomalacia C) Osteoporosis D) Scurvy
Answer: B. Osteomalacia is the adult form of vitamin D deficiency; rickets occurs in children.
4. Excessive vitamin D intakes can result in:
A) Liver damage B) Deposition of calcium in soft tissues C) Kidney stones D) All of these
Answer: B. Vitamin D toxicity causes hypercalcemia and calcium deposition in soft tissues.
5. Which of the following substances is a fat-soluble vitamin that has antioxidant activity?
A) Vitamin C B) Vitamin E C) Vitamin B12 D) Folate
Answer: B. Vitamin E is a fat-soluble antioxidant that protects cell membranes.
6. Which of the following foods is NOT a good source of vitamin E?
A) Plant oils B) Nuts C) Ground beef D) Seeds
Answer: C. Ground beef is not a good source of vitamin E; plant oils and nuts are.
7. A sign of vitamin E deficiency in humans is:
A) Night blindness B) Hemolysis C) Bleeding gums D) Beriberi
Answer: B. Vitamin E protects red blood cell membranes; deficiency causes hemolysis.
8. Vitamin K is primarily responsible for:
A) Vision B) Blood clotting C) Calcium absorption D) Antioxidant activity
Answer: B. Vitamin K assists with blood clotting.
9. Which vitamin is a provitamin that the body converts to vitamin A as needed?
A) Beta-carotene B) Lutein C) Zeaxanthin D) Lycopene
Answer: A. Beta-carotene is the most potent provitamin A carotenoid.
10. Performed vitamin A is found in:
A) Carrots B) Liver, fish oils, fortified milk, eggs C) Spinach D) Broccoli
Answer: B. Preformed vitamin A (retinol) comes from animal sources.
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11. Which fat-soluble vitamin is important for vision?
A) Vitamin D B) Vitamin E C) Vitamin A D) Vitamin K
Answer: C. Vitamin A is important for vision.
12. Excessive vitamin A intake during pregnancy can cause:
A) Birth defects B) Blindness C) Bleeding disorders D) Kidney failure
Answer: A. Vitamin A toxicity can cause birth defects.
13. Which vitamin is stored primarily in the liver?
A) Vitamin C B) Vitamin A C) Vitamin B12 D) Folate
Answer: B. Vitamin A is stored in the liver.
14. Vitamin D increases the deposition of which minerals in bones?
A) Iron and zinc B) Calcium and phosphorus C) Sodium and potassium D) Magnesium and
copper
Answer: B. Vitamin D increases calcium and phosphorus deposition in bones.
15. Which of the following factors results in LESS vitamin D synthesis?
A) Summer months B) Southern latitudes C) Older age D) More time in sun
Answer: C. Older individuals have reduced capacity for vitamin D synthesis due to thinner
skin and decreased precursor levels.
16. Dark-skinned individuals require more sun exposure to produce the same amount of
vitamin D because:
A) They have thinner skin B) Melanin reduces UVB penetration C) They have less cholesterol
precursor D) They sweat more
Answer: B. Melanin reduces UVB penetration, reducing vitamin D synthesis.
17. Which of the following factors results in MORE vitamin D synthesis?
A) Winter months B) Northern latitudes C) Summer months D) Older age
Answer: C. Summer months provide more intense UVB radiation.
18. The RDA for vitamin D for adults is:
A) 200 IU B) 400 IU C) 600–800 IU D) 1,000 IU
Answer: C. Adults require 600–800 IU daily.
19. Which vitamin is necessary for blood clotting?
A) Vitamin A B) Vitamin D C) Vitamin E D) Vitamin K
Answer: D. Vitamin K is essential for clotting factor synthesis.
20. Newborns are often given a vitamin K injection because:
A) Breast milk is low in vitamin K B) Newborns cannot absorb vitamin K C) Newborns lack
intestinal bacteria that synthesize vitamin K D) Both A and C
Answer: D. Breast milk is low in vitamin K, and newborns lack gut bacteria to synthesize it.
DHN 101 Exam 3 — 100 Original Practice Questions
Vitamin Basics & Fat-Soluble Vitamins (1–25)
1. Which of the following is an organic micronutrient?
A) Calcium B) Iron C) Vitamin C D) Sodium
Answer: C. Organic compounds contain carbon; vitamins are organic. Minerals are inorganic.
2. Which vitamin is synthesized in the skin upon exposure to sunlight?
A) Vitamin A B) Vitamin D C) Vitamin E D) Vitamin K
Answer: B. UVB rays convert 7-dehydrocholesterol to vitamin D3.
3. A condition associated with vitamin D deficiency in adults characterized by softening of
the bones is:
A) Rickets B) Osteomalacia C) Osteoporosis D) Scurvy
Answer: B. Osteomalacia is the adult form of vitamin D deficiency; rickets occurs in children.
4. Excessive vitamin D intakes can result in:
A) Liver damage B) Deposition of calcium in soft tissues C) Kidney stones D) All of these
Answer: B. Vitamin D toxicity causes hypercalcemia and calcium deposition in soft tissues.
5. Which of the following substances is a fat-soluble vitamin that has antioxidant activity?
A) Vitamin C B) Vitamin E C) Vitamin B12 D) Folate
Answer: B. Vitamin E is a fat-soluble antioxidant that protects cell membranes.
6. Which of the following foods is NOT a good source of vitamin E?
A) Plant oils B) Nuts C) Ground beef D) Seeds
Answer: C. Ground beef is not a good source of vitamin E; plant oils and nuts are.
7. A sign of vitamin E deficiency in humans is:
A) Night blindness B) Hemolysis C) Bleeding gums D) Beriberi
Answer: B. Vitamin E protects red blood cell membranes; deficiency causes hemolysis.
8. Vitamin K is primarily responsible for:
A) Vision B) Blood clotting C) Calcium absorption D) Antioxidant activity
Answer: B. Vitamin K assists with blood clotting.
9. Which vitamin is a provitamin that the body converts to vitamin A as needed?
A) Beta-carotene B) Lutein C) Zeaxanthin D) Lycopene
Answer: A. Beta-carotene is the most potent provitamin A carotenoid.
10. Performed vitamin A is found in:
A) Carrots B) Liver, fish oils, fortified milk, eggs C) Spinach D) Broccoli
Answer: B. Preformed vitamin A (retinol) comes from animal sources.
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11. Which fat-soluble vitamin is important for vision?
A) Vitamin D B) Vitamin E C) Vitamin A D) Vitamin K
Answer: C. Vitamin A is important for vision.
12. Excessive vitamin A intake during pregnancy can cause:
A) Birth defects B) Blindness C) Bleeding disorders D) Kidney failure
Answer: A. Vitamin A toxicity can cause birth defects.
13. Which vitamin is stored primarily in the liver?
A) Vitamin C B) Vitamin A C) Vitamin B12 D) Folate
Answer: B. Vitamin A is stored in the liver.
14. Vitamin D increases the deposition of which minerals in bones?
A) Iron and zinc B) Calcium and phosphorus C) Sodium and potassium D) Magnesium and
copper
Answer: B. Vitamin D increases calcium and phosphorus deposition in bones.
15. Which of the following factors results in LESS vitamin D synthesis?
A) Summer months B) Southern latitudes C) Older age D) More time in sun
Answer: C. Older individuals have reduced capacity for vitamin D synthesis due to thinner
skin and decreased precursor levels.
16. Dark-skinned individuals require more sun exposure to produce the same amount of
vitamin D because:
A) They have thinner skin B) Melanin reduces UVB penetration C) They have less cholesterol
precursor D) They sweat more
Answer: B. Melanin reduces UVB penetration, reducing vitamin D synthesis.
17. Which of the following factors results in MORE vitamin D synthesis?
A) Winter months B) Northern latitudes C) Summer months D) Older age
Answer: C. Summer months provide more intense UVB radiation.
18. The RDA for vitamin D for adults is:
A) 200 IU B) 400 IU C) 600–800 IU D) 1,000 IU
Answer: C. Adults require 600–800 IU daily.
19. Which vitamin is necessary for blood clotting?
A) Vitamin A B) Vitamin D C) Vitamin E D) Vitamin K
Answer: D. Vitamin K is essential for clotting factor synthesis.
20. Newborns are often given a vitamin K injection because:
A) Breast milk is low in vitamin K B) Newborns cannot absorb vitamin K C) Newborns lack
intestinal bacteria that synthesize vitamin K D) Both A and C
Answer: D. Breast milk is low in vitamin K, and newborns lack gut bacteria to synthesize it.
