Normal heart sounds are caused by which of the following events?
A) friction of blood against the chamber walls
B) closure of the heart valves
C) opening of the heart valves
D) excitation of the sinoatrial (SA) node
B
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Which of the following transport processes requires cell energy?
a. osmosis b. dialysis c. pinocytosis d. both A and B above
Lactic acid is the result of LDH (lactic acid dehydrogenase) mediated ________ of pyruvic acid with electrons taken from NADH + H+.
A. reduction B. hydrolysis C. oxidation D. phosphorylation
Action potentials are carried by the Purkinje fibers from the bundle branches to the ventricular walls.
a. true b. false
Which of the following describes how a presynaptic neuron would communicate a strong signal to a postsynaptic neuron?
A. Changing the destination of the action potentials B. Changing the direction the action potentials are traveling down its conductive segment C. Increasing the frequency of its action potentials D. Increasing the magnitude (voltage change) of each action potential