The first heart sound (lub) is produced by the closing of the ____ and ____ valves
a. aortic semilunar; pulmonary semilunar
b. right atrioventricular; aortic semilunar
c. left atrioventricular; pulmonary semilunar
d. right atrioventricular; left atrioventricular
e. mitral; left atrioventricular
d
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In oxidative phosphorylation within a prokaryote, electrons are passed through a series of carriers to an organic molecule at the end of the transport chain.
a. True b. False
Sperm are formed from the direct maturation
of a. sperm mother cells. b. spermatids. c. spermatogonial cells. d. primary spermatocytes. e. secondary spermatocytes
To a person studying utilization of classroom space on campus, the most useful data concerning
students in a classroom would be expressed by the number of a. total individuals. b. individuals per square yard. c. individuals per room. d. rooms per building. e. students of each age.
Which of the following is/are TRUE regarding serotonin?
a. serotonin is synthesized from tryptophan b. serotonin is a peptide c. serotonin regulates anxiety and aggression d. serotonin is a neurotransmitter e. a, c, and d