Normal Cardiac Muscle Is Similar to Normal Skeletal Muscle in Terms

Multiple Choice

Normal cardiac muscle is similar to normal skeletal muscle in terms of

A) the duration of the action potentials, which last 250-300 msec.
B) the duration of the resulting contractions.
C) the refractory period, which continues until relaxation is under way.
D) the appearance of calcium among the myofibrils.
E) the appearance of summation of twitches.