The first heart sound is heard when the
A) AV valves open.
B) AV valves close.
C) semilunar valves close.
D) atria contract.
E) blood enters the aorta.
Answer: B
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The main hormone secreted by the adrenal medulla in response to sympathetic stimulation is __________.
Fill in the blank(s) with the appropriate word(s).
The term basic multicellular unit (BMU) refers to
A. the clusters of chondrocytes within the metaphysis that will be converted to bone. B. the osteoblasts found in the deepest layer of the periosteum, which are involved in appositional growth. C. group of osteoblasts and osteoclasts that work together during bone remodeling.
The number of job openings (n) divided by the number of job applicant (N) is known as
A. Selection ratio B. 4/5ths rule C. Base rate D. Cut score
Which functional class of neurons lies entirely within the central nervous system?
A. Unipolar neurons B. Motor neurons C. Interneurons D. Sensory neurons E. Bipolar neurons