Human Heart

Question 1

What is the role of the pulmonary artery?

Answer 1

Carries deoxygenated blood from right ventricle to the lungs

Question 2

What is the role of the vena cava?

Answer 2

Carries deoxygenated blood from body to the right atria

Question 3

What is the role of the aorta?

Answer 3

Carries oxygenated blood from left ventricle to body

Question 4

What is the role of the pulmonary vein?

Answer 4

Carries oxygenated blood from lungs to left atria

Question 5

What is the role of the semilunar valves?

Answer 5

Open when pressure in ventricles is greater than in blood vessels

Question 6

What is the role of the atrioventricular valves?

Answer 6

Open when pressure in atria is greater than ventricles

Question 7

What is the role of the SAN?

Answer 7

Initiates heart beat

Question 8

What is the role of the AVN?

Answer 8

Delays the impulse, allowing atria to contract before the ventricles

Question 9

What is the role of the bundle of His?

Answer 9

Carries the impulse to the Purkyne fibres

Question 10

What is the role of the non-conductive tissue?

Answer 10

Stops impulse from SAN reaching ventricles

Question 11

What are the three stages of a heart beat?

Answer 11

1. Atria contract
   - Pressure higher in atria than ventricles
   - AV valves open
   - SL valves close
2. Ventricles contract
   - Pressure is highest in the ventricles
   - AV valves close
   - SL valves open
3. Atria and ventricles relax
   - Pressure is higher in atria (filling)
   - AV valves open
   - SL valves close