Cardiac muscle cells
A. have smooth ER but no T tubules.
B. form the heart valves.
C. are maintained by an extensive capillary network.
D. develop a significant oxygen debt during systole.
E. do not contain actin and myosin like skeletal muscle cells.
C
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Fill in the blank(s) with correct word
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Why doesn't semen enter the urinary bladder during ejaculation?
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