41.Which of the following can the body use to synthesize vitamin D?

a.bone

b.carotene

c.tryptophan

d.exposure to sunlight

42.In what tissue(s) must a molecule of vitamin D be chemically altered to yield a compound that is fully active?

a.liver and kidney

b.liver and intestines

c.kidney and stomach

d.intestines and stomach

43.Which of the following terms is another name for vitamin D?

a.calmodulin

b.calcitonin

c.cholecystokinin

d.calcimar

44.Which of the following compounds is known to function as a hormone?

a.vitamin D

b.vitamin K

c.phylloquinone

d.alpha-tocopherol

45.The major target organs for activated vitamin D include all the bones and which one of the following organs?

a.liver

b.pancreas

c.kidney

d.gallbladder

46.What is/are the main function(s) of vitamin D?

a.promoting secretion of calcitonin

b.promoting synthesis of 7-dehydrocholesterol

c.promoting synthesis of carotenoids and controlling absorption of fat-soluble vitamins

d.promoting calcium and phosphorus absorption and promoting calcium mobilization from bone

47.Which vitamin is likely deficient in a child with bowed legs?

a.vitamin A

b.vitamin K

c.vitamin E

d.vitamin D

48.What is the name of the vitamin D-deficiency disease in adults?

a.rickets

b.osteomalacia

c.keratomalacia

d.hyperkeratosis

49.What population group is at highest risk for osteomalacia?

a.infants

b.elderly men

c.adult women

d.children ages 2-12 years

50.In what system would the effects of a vitamin D deficiency be most readily observed?

a.nervous system

b.skeletal system

c.muscular system

d.circulatory system