Which of the following is involved in the gradation of muscle contraction?
a. variation in the number of motor units activated
b. variation in the frequency of action potentials initiated in each muscle fiber
c. variation in the size of the action potentials initiated in each muscle fiber
d. both (a) and (b) above.
e. all of these answers.
D
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A. contraction B. latent C. relaxation
The ________ is the liquid portion of the cell between the plasma membrane and nucleus.
A. peroxisome B. phospholipids C. cytosol D. cytoskeleton
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A. Excitability B. Secretion C. Conductivity D. Permeability
All cardiac veins eventually drain into the coronary sinus for return of the blood from the myocardium to the right atrium.
Answer the following statement true (T) or false (F)