List of top Zoology Questions on Cardiovascular system

Assertion (A): Reduced blood supply to heart muscles causes ischemia which results in chest pain.
Reason (R): It is a warning signal of deprivation of blood supply to heart muscles.
Assertion (A): Angina pectoris occurs due to transient myocardial ischemia without causing permanent damage to heart muscles. Reason (R): In coronary artery disease, narrowing of coronary arteries reduces blood supply to myocardium.
Choose the correct sequence of events during a Cardiac cycle:

Match the column I with Column II.

Sino-Atrial Node (SAN) is situated in