Question

57. The contractive phase of the heartbeat is a. diastole. b. heart rate. c. blood pressure. d. systole. 58. The natural pacemaker of the heart is the a. bundle branch. b. bundle of His. c. sinoatrial node. d. atrioventricular bundle. 59. The state where the cardiac cells are resting. a. Depolarized state b. Polarized state c. Repolarized state d. Artifact state e. Isoelectric state 60. The state where the cardiac cells are recovering. 220 SHEETS n Holds More Sheets Pound Ring

Answer 1

Ans) 57) d. Systole

Explaination:

- The period of contraction that the heart undergoes while it pumps blood into circulation is called systole.

58) c. Sinoatrial node

Explaination:

59)

- The sinoatrial (SA) node or sinus node is the heart's natural pacemaker. It's a small mass of specialized cells in the top of the right atrium (upper chamber of the heart). It produces the electrical impulses that cause your heart to beat.

59) a. Depolarized state

Explaination:

- Repolarization, “electrical diastole”, occurs as the inside of the cardiac cell recovers to return to its normal negative electrical state. Myocardial cells go back to their resting states and the cardiac muscle cells relax. The entire process of depolarization and repolarization is known as the action potential.

60) c. Repolarized state

Explaination:

- Repolarization, “electrical diastole”, occurs as the inside of the cardiac cell recovers to return to its normal negative electrical state. Myocardial cells go back to their resting states and the cardiac muscle cells relax. The entire process of depolarization and repolarization is known as the action potential.