If we were able to artificially alter the membrane permeability of pacemaker cells so that sodium influx is more rapid, ________
A) tetanic contraction would occur due to the short absolute refractory period of cardiac muscle
B) threshold is reached more quickly and heart rate would increase
C) potassium channels compensate and no change in heart rate would occur
D) heart rate would decrease, but blood pressure would rise due to the excess sodium present
B
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Answer the following statement true (T) or false (F)
Good general dietary advice for athletes is to eat
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