11. After heart transplantation, B’s heart rate is slower than normal and relies on intrinsic sinus rhythm. If B goes hiking, can his heart rate increase when he climbs hills?
a. No, the cardiac nerves have been cut and do not regenerate.
b. No, vagus tone increases.
c. Yes, from circulating epinephrine
d. Yes, because of vagal withdrawal
e. Choices (a) and (d).