The first heart sound ("lubb") is associated with
A) atrial systole.
B) closing of the atrioventricular valves.
C) opening of the atrioventricular valves.
D) closing of the semilunar valves.
E) opening of the semilunar valves.
B
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Indicate whether the statement is true or false
A demyelinating disease affects ________
A) perineurium B) endoneurium C) Schwann cells D) epineurium
The portion of the brain involved primarily with vision is the
A. insula. B. temporal lobe. C. frontal lobe. D. parietal lobe. E. occipital lobe.
Sympathetic innervation of the hearta: increases the heart rate.b: decreases the heart rate.c: increases the force of contractions.d: decreases the force of contractions.e: has no effect on contraction force.
A. b, d B. a, d C. a, e D. b, e E. a, c