The atrioventricular valves (tricuspid and bicuspid) open when the papillary muscles:
A) contract
B) relax
Answer: B) relax
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A neuron has received a signal, causing ion channels to open in the cell membrane, letting positively charged ions flow in. This has caused the membrane potential to change suddenly from –70 to +50 millivolts. This will cause a (an) _____ to occur.
a) resting state b) action potential c) negative charge d) positive charge
Contrast the functions of the following pairs: thalamus and hypothalamus; cerebellum and basal nuclei
What will be an ideal response?
A long bone is covered externally with a sheath called the ________, whereas the marrow cavity is lined with the ________.
A. epiphysis; diaphysis B. compact bone; spongy bone C. diaphysis; epiphysis D. endosteum; periosteum E. periosteum; endosteum
Which of the following adult structures is not derived from the same primary germ layer as the others?
A. Muscles B. Bones C. Blood vessels D. Nerves