Select the correct statement about the function of myocardial cells
A) The refractory period in skeletal muscle is much longer than that in cardiac muscle.
B) Cardiac muscle cells are innervated by sympathetic, parasympathetic, and somatic nerve fibers so that the nervous system can increase heart rate.
C) The entire heart contracts as a unit or it does not contract at all.
D) The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction.
C
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The anatomic term for the calf is
A. crural.?B. popliteal.?C. tarsal.?D. carpal.?E. sural.
The cells that respond to environmental stimuli are ________
Fill in the blank(s) with correct word
What does not happen to a carbon dioxide molecule once it enters the bloodstream?
A) It is converted to a molecule of carbonic acid. B) It binds to the protein portion of hemoglobin molecules within red blood cells. C) It dissolves in plasma. D) It is converted by carbonic anhydrase. E) It binds to heme groups in hemoglobin.
The potential space between the parietal and visceral pleura is the ____________________
Fill in the blank(s) with correct word