The Heart LO1

Question 1

What is the heart made of?

Answer 1

The heart is made from specialised cardiac muscle that does not tire like other muscles around the body.

Question 2

How many chambers of the heart are there?

Answer 2

There are two upper chambers are called the right atrium and the left atrium.
The two lower lobes are called the right and left ventricles. The left ventricle has the thickest muscular wall as it has to pump blood from the heart to the rest of the body.

Question 3

The four chambers have a major blood vessel entering and leaving, what are the major blood vessels?

Answer 3

The aorta, pulmonary artery, vena cava and the pulmonary vein

Question 4

What is the aorta?

Answer 4

It is the main artery of the body; it leaves the heart from the left ventricle

Question 5

What is the pulmonary artery?

Answer 5

It carries the deoxygenated blood form the heart to the lungs

Question 6

What is the vena cava?

Answer 6

It is the superior (anterior) vena cava is one of the largest veins in the body

Question 7

What is the pulmonary vein?

Answer 7

It carries oxygenated blood from the lungs to the left atrium of the heart

Question 8

There are 4 valves in the heart. They permit blood to flow one way only. What are the valves?

Answer 8

The valves are tricuspid, bicuspid, pulmonary and aortic valve

Question 9

What is the tricuspid?

Answer 9

the first valve that blood encounters as it enters the heart, the tricuspid allows blood to flow only from the right atrium to the right ventricle

Question 10

What is the bicuspid valve?

Answer 10

This is also known as the mitral valve. This allows blood to flow from the left atrium to the left ventricle

Question 11

What is the pulmonary?

Answer 11

The pulmonary is at the opening from the right ventricle and stops blood going back from the pulmonary artery into the heart

Question 12

What is the aortic valve?

Answer 12

It is found at the exit of the left ventricle where the aorta begins

Question 13

Why is the heart sometimes referred as a double pump?

Answer 13

It pumps blood through two separate circulatory systems, the pulmonary and the systemic circulation.

Question 14

What is the pulmonary circulation?

Answer 14

this is when the right side of the heart receives deoxygenated blood from the body and pumps it to the lungs

Question 15

What is systemic circulation?

Answer 15

this is when the left side of the heart receives oxygenated blood form the longs and pumps it to the rest of the body

Question 16

What is deoxygenated blood?

Answer 16

blood that has little or no oxygen, but does contain carbon dioxide

Question 17

What is oxygenated blood?

Answer 17

blood that contains oxygen

Question 18

How does the blood flow through the heart?

Answer 18

• blood from the lungs, which is oxygenated, returns to the heart via the pulmonary vein and enters the left atrium
• blood passes through the bicuspid (mitral) valve into the left ventricle
• blood is forced out of the aorta and carries the oxygenated blood to the rest of the body
• deoxygenated blood returns from the body to the right atrium via the superior and inferior vena cava
• the blood is then squeezed through the tricuspid valve into the right ventricle
• blood is forced through the pulmonary artery, which carries the deoxygenated blood to the lungs

Question 19

the cardiac cycle

Answer 19

at rest a healthy adult heart is likely to beat at a rate of 60 to 80 beats per minute. During each heartbeat or ‘cardiac cycle’ the heart contracts (systole) and then relaxes (diastole). So on average the cardiac cycle is repeated 70 times a minute.

Question 20

What are the stages of the cardiac cycle?

Answer 20

-atrial systole- contraction of the right and left atria
-ventricular systole- contraction of the ventricles
-complete cardiac diastole- relaxation of the atria and ventricles