The "tanning" effect (darkening of the skin) that occurs when a person is exposed to the sun is due to the increased presence of ________
A) melanin
B) keratin
C) oil
D) epidermis dendritic cells
E) sweat
Anser: A) melanin (due to the pigment: increased production of melanin that helps to block ultraviolet lights.)
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Collectively, reactions that build new molecules are known as
A) anabolic. B) metabolic. C) synthetic reactions. D) exchange reactions. E) catabolic.
Hormones called ________ are involved in regulation of white blood cell populations.
Fill in the blank(s) with the appropriate word(s).
Ventricular systole includes the periods of
a. isometric contraction and ventricular ejection. b. isovolumetric contraction and ventricular ejection. c. isometric contraction and end-systolic volume. d. isovolumetric contraction and end-systolic volume. e. none of these
The effectiveness of positive-pressure ventilations when treating a head-injured patient can ONLY be determined by:
A. immediate reassessment following the intervention. B. a neurosurgeon or emergency department physician. C. reassessing the patient's blood pressure after at least 10 minutes. D. noting a decrease in the heart rate during ventilations.