Which of the following statements regarding intrinsic regulation of the heart is true?
A. If cardiac muscle cells are slightly stretched, they have a stronger contraction force.
B. The heart's pumping effectiveness is greatly influenced by small changes in afterload.
C. Stretching the SA node will decrease generation of action potentials in the node.
D. If cardiac muscle cells are slightly stretched, they have a weaker contraction force.
E. Decreased venous return increases cardiac output.
Answer: A
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Which of the following is FALSE regarding single-unit smooth muscle cells?
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