Which statement best explains why severe B vitamin deficiencies can lead to fatigue?

Which statement best explains why severe B vitamin deficiencies can lead to fatigue?
 a. B vitamins are a source of energy (calories).
  b. Absorption of carbohydrate is decreased.
  c. Oxygen needed for energy metabolism cannot be transported to the cells.
  d. Coenzymes needed for energy metabolism are produced in insufficient amounts.

Q. 2

Which of the following statements is true about B-complex vitamins?
 a. These vitamins contain energy and are directly associated with fatigue.
  b. These vitamins play an indirect role in energy production.
  c. Studies show that sub-clinical deficiencies typically result in fatigue.
  d. Athletes generally improve performance when they take a low-dose supplement.

Q. 3

At what point do enzymes and coenzymes function at maximum velocity?
 a. 75 of tissue saturation
  b. 100 of tissue saturation
  c. 110 of tissue saturation
  d. 125 of tissue saturation

Q. 4

Which of the following describes the basic function of a coenzyme?
 a. Attaches to RNA to assist in the synthesis of an enzyme
  b. Attaches to cell membranes to assist in the uptake of an enzyme
  c. Attaches to an enzyme, which allows for the activation of the enzyme
  d. Attaches to an enzyme, which allows for the transportation of the enzyme

Q. 5

When supplemented at high doses, the vitamin that may be toxic to nervous tissue is:
 a. thiamin.
  b. riboflavin.
  c. niacin.
  d. vitamin B6.

Q. 6

According to the current body of scientific research, what is known about vitamin A toxicity?
 a. No reports in industrialized countries
  b. Number of cases is extremely small
  c. Number of cases is moderate and increasing
  d. Number of cases is large but effects are minor

Q. 7

Overconsumption of which vitamin is most likely to result in toxicity?
 a. Vitamin A (retinol)
  b. Vitamin E (alpha-tocopherol)
  c. Vitamin B1 (thiamin)
  d. Vitamin B12 (cobalamin)

Q. 8

In general, how long does it take vitamin toxicities to develop?
 a. Several days to a few weeks
  b. Several weeks to a few months
  c. Several months to a few years
  d. Many decades

Q. 9

The vitamin supplement that is considered to have the lowest risk but highest benefit is:
 a. vitamin A.
  b. retinol.
  c. folic acid.
  d. vitamin B12.

Q. 10

Which of the following poses the greatest health risk when consumed as a high-dose supplement?
 a. Vitamin A
  b. Vitamin C
  c. Vitamin E
  d. Niacin