1. B – The Cardiovascular System
The structure and function of arteries, capillaries and veins
The structure and function of the heart
Pathology of cardio vascular disease (CVD)
Blood glucose levels and obesity

2. KA 6: The structure and function of the heart
2.6 Key Topics
REVISION:
Structure of the heart
(D) Blood Pressure
(A)
Cardiac function and cardiac output
(B) Cardiac cycle
(C)
The structure and function of cardiac conducting system

3. KA 6b: Learning Outcomes
State what is meant by the cardiac cycle
Define and describe what happens during atrial systole
Define and describe what happens during ventricular systole
Define and describe what happens during diastole
Describe the action of AV and SL valves during the cardiac cycle
Describe the changes in pressure during the cardiac cycle
Interpret graphs of pressure changes in heart and blood vessels

4. 2 minutes – think/pair/share
This animation shows REPEATED cardiac cycles…
What do think the cardiac cycle is?
What do you think makes ONE cycle?

5. The Cardiac Cycle
The cardiac cycle is the name of the pattern of contraction (systole) and relaxation (diastole) in one complete heartbeat.

6. The Cardiac Cycle ATRIAL SYSTOLE
Atrial systole is when the atria contract to transfer blood through the open atrio-ventricular (AV) valves to the ventricles.

7. The Cardiac Cycle VENTRICULAR SYSTOLE
Ventricular systole closes the AV valves. The ventricle contract and pump the blood out through the open semi lunar (SL) valves to the aorta and pulmonary artery.

8. The Cardiac Cycle DIASTOLE
During diastole blood returning to the relaxed atria flows into the relaxed ventricles. In diastole the higher pressure in the arteries closes the SL valves.

9. The Cardiac Cycle

10. Cardiac Cycle Videos https://www.youtube.com/watch?v=5tUWOF6wEnk

11. Task: Use your card sort to describe what is going on in this graph!
“DUB”
Blood flows from the atria into the ventricles through the atrioventricular valves.
The atria contract.
The semilunar valves close.
The ventricles contract.
The atrioventricular valves close.
Blood flows through the semilunar valves into the aorta (from the left ventricle) and the pulmonary artery (from the right ventricle).
Heart muscle relaxes.
The semilunar valves are closed.
Blood flows into the atria (right – from vena cava, left – from pulmonary vein).
The atrioventricular valves are open to allow blood to move into the ventricles.
“LUB”
The atrioventricular valves are open to allow blood to move into the ventricles.
The atria contract.
The SL valves open.
The AV valves close.
The ventricles contract
Heart muscle relax
The SL valves are closed

12. Colour code each of the 3 lines!
The Cardiac Cycle
The opening and closing of the AV and SL valves are responsible for the heart sounds heard with a stethoscope (‘lub’ and ‘dub’).
TASK:
Colour code each of the 3 lines!

13. KA 6b: Learning Outcomes
State what is meant by the cardiac cycle
Define and describe what happens during atrial systole
Define and describe what happens during ventricular systole
Define and describe what happens during diastole
Describe the action of AV and SL valves during the cardiac cycle
Describe the changes in pressure during the cardiac cycle
Interpret graphs of pressure changes in heart and blood vessels