Question

The blood vessel which supply oxygenated blood to cardiac tissue is
a. Coronary artery
b. Coronary vein
c. Coronary sinus
d. Pulmonary vein

Answer 1

Hint: The process of circulation of blood in the blood vessels of the heart muscle or myocardium is called Coronary circulation. The oxygen-rich blood delivered by the vessels to the myocardium are known as coronary arteries. The cardiac veins are the vessels which remove the deoxygenated blood from the heart muscle.

Complete answer:
- The blood from the pulmonary veins and vena cava flows into the left and the right ventricle respectively through the left and right atria.
- The atrial systole occurs when both the atria undergo a simultaneous contraction.
- This is due to action potential generated by SAN.
- The AVN and AV bundle generates an action potential which is conducted to the ventricular side from where the bundle of His transmits it through the entire ventricular muscle
- The cardiac veins include the great cardiac vein, the middle cardiac vein, the small cardiac vein and the anterior cardiac veins.
- The deoxygenated blood from those veins that collect deoxygenated blood from the wall of the heart finally gets collected in coronary sinus.
- The deoxygenated blood from the muscles of the heart to the right atrium is carried by coronary veins.
- The oxygenated blood is supplied to the muscles of the heart or the cardiac tissue by the coronary artery.
- The deoxygenated blood from the right ventricle of the heart to lungs is carried through the pulmonary artery.

Hence, the correct answer is option (A).

Note: The heart beats 72 times per minute. The length of the cardiac cycle is 0.8 seconds. After each cardiac cycle, each ventricle pumps out approximately 70 mL of blood which is called the stroke volume. The cardiac output is measured as stroke volume multiplied by the heart rate (no. of beats per min which averagely is 5000 mL or 5 litres in a healthy individual.