Heart Validation

Question 1

What is the heart

Answer 1

Pump that pushes blood around the body

Question 2

What are th purposes of each chamber of the heart

Answer 2

Right Ventricle: pumps blood to the lungs
Right Atrium: receives blood from body and passes to right ventricle.
Left Ventricle: pumps blood to the body
Left Atrium: receives blood from the lungs and passes to left ventricle

Question 3

What are the valves in the heart

Answer 3

Atrioventricular Valves
- tricuspid valve: btwn RV and ra
- bicuspid valve: btwn LV and la

Semilunar Valves:
- Pulmonary Valve: btwn RV and Pa
- Aortic Valve: btwn LV and aorta

Question 4

What are arteries and their purpose?

Answer 4

Arteries carry blood away from heart.
- Walls contain smooth muscle and elastic fibres, allowing them to stretch when ventricles contract and push blood into arteries.
- Are able to contract to reduce flow of blood to an organ, called vasoconstriction.
- Conversely also, called Vasodilation.
- veins divide into arterioles, which supply blood to capillaries.

Question 5

Capillaries

Answer 5

Link between arteries and veins.
Wall is one cell thick, allowing substances to pass easily btwn blood and surrounding cells through diffusion.
Function: Carries the requirements of cells to those cells through the blood, and carries waste products from the cells to the blood (CO2).

Question 6

Veins

Answer 6

Carry blood towards heart, capillaries join into venules which then join up to make larger veins. These end in the
- inferior and superior vena cava, bring blood from body to right Atrium.
- Pulmonary Veins: Bring blood from lungs to the left atrium, there are 4 two for each lung.

Question 7

Formula for Cardiac Output

Answer 7

Cardiac output = stroke volume X heart rate

Question 8

What is the cardiac cycle?

Answer 8

The caardiac cycle is the sequence of events that occurs in one complete beat of the heart.

When heart muscles contract, is called systole.
Filling phase as muscles relax is called diastole.

During diastole, the atria fill with blood and the ventricles also receive blood as the valves between them are open.

Atrial systole (contraction of atria) follows and forces remaining blood into ventricles. Atria then relax and refill, while ventricles contract in ventricular systole.

This forces blood into the arteries. Both atria and ventricles contract simultaneously.