The heart - structures and functions

Question 1

where is the right atrium and what does it do?

Answer 1

Receives deoxygenated blood from the body through the superior and inferior vena cavae. It then pumps the blood into the right ventricle.

Question 2

Where is the right ventricle and what does it do?

Answer 2

Pumps deoxygenated blood into the pulmonary arteries, which carry it to the lungs for oxygenation.

Question 3

Where is the left atrium and what does it do?

Answer 3

Receives oxygenated blood from the lungs through the pulmonary veins and pumps it into the left ventricle.

Question 4

Where is the left ventricle and what does it do?

Answer 4

Pumps oxygenated blood into the aorta, which then distributes it throughout the body.

Question 5

What is the semi-lunar valve and where is it?

Answer 5

Location: Between the right ventricle and the pulmonary artery.

Function: Prevents backflow of blood from the pulmonary arteries into the right ventricle after contraction.

Question 5

What is the Tricuspid Valve and where is it?

Answer 5

Location: Between the right atrium and right ventricle.

Function: Prevents backflow of blood from the right ventricle into the right atrium when the ventricle contracts.

Question 6

What is the Mitral valve and where is it?

Answer 6

Location: Between the left atrium and left ventricle.

Function: Prevents backflow of blood from the left ventricle into the left atrium during ventricular contraction.

Question 7

what is the aortic valve and where is it?

Answer 7

Location: Between the left ventricle and the aorta.

Function: Prevents backflow of blood from the aorta into the left ventricle after contraction.

Question 8

What is the superior vena cava?

Answer 8

Function: Carries deoxygenated blood from the upper half of the body (head, neck, and arms) to the right atrium.

Question 9

What is the inferior vena cava?

Answer 9

Function: Carries deoxygenated blood from the lower half of the body (abdomen and legs) to the right atrium.

Question 10

What are the pulmonary arteries?

Answer 10

Function: Carry deoxygenated blood from the right ventricle to the lungs for oxygenation.

Question 11

What are the pulmonary veins?

Answer 11

Function: Carry oxygenated blood from the lungs to the left atrium.

Question 12

What is the aorta?

Answer 12

Function: The largest artery in the body, it carries oxygenated blood from the left ventricle to the rest of the body.

Question 13

What are the coronary arteries?

Answer 13

Function: Supply oxygen-rich blood to the heart muscle (myocardium). The left and right coronary arteries arise from the base of the aorta.

Question 14

What are the coronary veins?

Answer 14

Function:
Return oxygen-rich blood from theheart muscle (myocardium), back to the heart. Smaller veins fuse to become a large THIN WALLED vein called:

CORONARY SINUS

This empties blood directly into the right atrium , where it will restart the cycle

Question 15

What is the endocardium?

Answer 15

Location: The innermost layer, lining the chambers of the heart and covering the heart valves.

Function: Provides a smooth, frictionless surface for blood to flow through the heart chambers.

Question 16

What is the myocardium?

Answer 16

Location: The middle layer, composed of cardiac muscle.

Function: The thick muscular layer responsible for contracting and pumping blood out of the heart.

Question 17

What is the epicardium?

Answer 17

Location: The outer layer of the heart, also considered the visceral layer of the pericardium.

Function: Provides a protective layer and contains blood vessels that supply the heart muscle (coronary vessels).

Question 18

What is the sinoatrial node (SA node)

Answer 18

Location: In the right atrium near the superior vena cava.

Function: Known as the “natural pacemaker” of the heart, it initiates electrical impulses that cause the heart to beat.

Question 19

What is the atrioventricular node?

Answer 19

Location: At the junction of the atria and ventricles.

Function: Receives the electrical impulse from the SA node, delays it slightly to allow the atria to contract fully before the ventricles do.

Question 20

What is the bundle of his?

Answer 20

Location: Passes from the AV node into the interventricular septum.

Function: Carries the electrical impulses from the AV node toward the ventricles.

Question 21

What are the right and left branches?

Answer 21

Location: Extend from the Bundle of His down the sides of the interventricular septum.

Function: Conduct the electrical impulses to the right and left ventricles, respectively.

Question 22

What are the purkinje fibres?

Answer 22

Location: Spread throughout the ventricular walls.

Function: Transmit the electrical impulse to the muscle cells of the ventricles, causing them to contract and pump blood to the lungs and body.