Answer Happy

27) 27) Why is there not a resting membrane potential in autorhythmic cells? A) The K+ channels are not finished closing when the Cat channels open B) The Cat channels open too early C) The Ir channels are open when repolarization ends D) The If channels are not open when depolarization begins 28) 28) Which of these is the result of the action potential in skeletal muscle fibers? A) RyR channels in the SR are pulled open B) Myosin heads bind to actin molecules C) The Cat+ATPase becomes active D) Myosin heads pull on actin molecules 29) 29) Which of the following is the most accurate description of pulse pressure? A) the pressure exerted by the volume of blood always in the artery B) the pulse wave created by the left ventricle's contraction C) the increased stretch of the arterial wall from the pulse wave D) the average pressure over time of blood in the arteries