The "tanning" effect (darkening of the skin) that occurs when a person is exposed to the sun is due to ________.
A) melanin
B) keratin
C) oil
D) Langerhans cells
E) sweat
Answer: A) melanin
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________ yield about 4 kcal/g when completely oxidized, whereas ________ yield about 9 kcal/g
A) Proteins and carbohydrates; fats B) Proteins; fats and carbohydrates C) Carbohydrates and fats; proteins D) Carbohydrates; fats and proteins E) Fats; carbohydrates and proteins
During the plateau phase of the sexual response, the glans and clitoris swell as the deep arteries dilate and the ________ engorge with blood.
A. uterine walls B. vestibular glands C. corpus spongiosum D. corpora cavernosa E. vaginal walls
__________ is a cytochrome P450 enzyme that metabolizes androgens to estrogens
A) Aromatase B) Phenylethanolamine N-methyltransferase C) Tyrosine hydroxylase D) Steroid 22-hydroxylase Fill in the blank with the correct answer.
The primary goal of the immune response is
A. stimulation of mitotic activity in order to replace cells damaged by infection. B. maintenance of the proper ionic balance between lymph and blood. C. destruction or inactivation of pathogens and foreign material. D. removal of antibodies from lymph and lymphatic organs. E. reduction of the number of circulating memory lymphocytes.