Eskimos wear a great deal of clothing and have limited exposure to U.V. light, but do not suffer from vitamin D deficiency. A possible explanation is,
A. their exposure to U.V. light in the summer will last for a year.
B. they do not need vitamin D.
C. their bodies produce vitamin D another way.
D. they get enough vitamin D in their diet of fish and marine mammals.
E. they do not require sunlight for vitamin D formation.
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Question 2) On coming inside from the cold, students notice that their cheeks are red. This results from
A. dilation of the blood vessels in the dermis of the cheeks.
B. constriction of the blood vessels in the epidermis of the cheeks.
C. increased permeability of superficial vessels.
D. constriction of the sweat glands in the cheeks.
E. damage to the epidermis by the cold.
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Question 3) Which vitamin begins its synthesis in the skin exposed to ultraviolet light?
A. vitamin C
B. vitamin E
C. vitamin B
D. vitamin D
E. vitamin A
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Question 4) By reducing body temperature during hot weather, skin helps to maintain
A. blood pH.
B. body temperature homeostasis.
C. brain activity.
D. body structure.
E. blood volume.
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Question 5) Which of the following will help cool the body?
A. decreased blood flow to the skin
B. absorption of excess sweat
C. evaporation of sweat from the skin's surface
D. absorption of ultraviolet light rays by the skin
E. contraction of the arrector pili muscles
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Question 6) Which of the following statements concerning vitamin D is false?
A. Vitamin D is necessary for the formation of bones and teeth.
B. Vitamin D causes the kidney to excrete calcium.
C. Vitamin D is important for calcium homeostasis.
D. Vitamin D is necessary for the uptake of calcium from the intestine.
E. Vitamin D begins its synthesis in the skin when the skin is exposed to ultraviolet light.
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Question 7) Due to the contraction of smooth muscle in the walls of the dermal blood vessels,
A. body heat is conserved.
B. more blood enters into the heart.
C. more blood flows to the skin.
D. body temperature tends to drop in that area.
E. the blood vessels become dilated.
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Question 8) An abrasion of the skin results in which of the following?
A. fluid retention by the kidney
B. increased melanin production
C. portal of entry for microorganisms
D. loss of cell regeneration ability
E. irreversible damage to the epidermis
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Question 9) An increase in body temperature causes
A. sweating.
B. an increase in melanin production.
C. an increase in keratinization of the skin.
D. arterioles in the dermis to constrict.
E. arrector pili muscles to contract.
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Question 10) Intact skin provides protection because
A. the skin enhances water loss from the body.
B. macrophages roam in the epidermis.
C. its secretions keep the skin slightly alkaline.
D. the skin contains components of the excretory system.
E. it forms a physical barrier against the entry of microbes.
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