1. The Structure of The Heart

2. The Heart Muscular pump, about the size of a clenched fist
Made up of a special muscle called Myocardium
This can contract continuously without getting tired
Main purpose is to drive blood through the arteries
This delivers blood to the working muscles and other tissues.

3. Task…
Find a picture of a blank heart (that is suitable to annotate) and upload it to a blank document.
Then do some light background research on the different labels of the heart including…
Structure of the cardiovascular system- heart:
Atria
Ventricles
Bicuspid valve and tricuspid valve
Aortic valve and pulmonary valve
Aorta and vena cava – superior and inferior
Pulmonary vein and pulmonary artery

4. The Heart continued
The Heart sits in a twin layered sac known as the Pericardium
Filled with pericardial fluid
Prevents friction as your heart beats.

5. The Heart continued Epicardium (Outer)
The heart wall has 3 layers
Epicardium (Outer)
Myocardium (middle layer and most of the heart wall)
Endocardium (The inner layer)

6. Ventricles Atria Lower chambers of the heart
Upper chambers of the heart
Receive blood.
Right Atrium – receives deoxygenated blood from the body (Via the Vena Cava)
Left Atrium – receives oxygenated blood from the lungs (Via the pulmonary Vein)
Ventricles
Lower chambers of the heart
They have thicker walls and are stronger
Job is to pump the blood
Right Ventricle pumps blood to the lungs (pulmonary circulation)
Left ventricle pumps blood to the body (systemic circulation)

7. Valves Tricuspid Valve Bicuspid Valve Aortic Valve Pulmonary Valve
Also known as the mitral valve
Aortic Valve
Pulmonary Valve
All valves make sure that the blood flows in one direction, and there is no back flow
Chordae Tendineae
Cord like tendons that connect to the tricuspid and bicuspid valves
Ensure the valves stay the right way round and keep the blood flowing in the same direction.

8. Aorta and Vena Cava The largest Artery is the Aorta
The largest vein is the Vena Cava
Carries blood directly into the heart from the body
Superior vena cava
brings blood from the upper body
Inferior Vena Cava
Brings blood from the lower body.
The largest Artery is the Aorta
Carries oxygenated blood directly out of the heart to the body tissues

9. Pulmonary Circulation
Pulmonary Artery
Carries deoxygenated blood from the heart to the lungs.
It is the only artery that carries deoxygenated blood
Pulmonary Vein
Carries oxygenated blood from the lungs to the heart
It is the only vein that carries oxygenated blood.

10. The Heart = Double pump
To describe the flow of blood around the heart and the body, you will need to mention that the heart is made up of two pumps
Pulmonary circulation
Pumps blood to and from the lungs
Systemic circulation
Pumps blood around the body

11. Passage of blood flow
Blood flows into and out of the heart and around the body in one direction.
The heart is split into two distinct pumps by the Septum.
This makes sure that the oxygenated and deoxygenated blood don’t mix.
When describing the passage of blood flow around the heart, it is best to use a diagram and start on the right side of the heart.

12. The right side of the heart
Blood enters the heart (when it is relaxed) via the vena cavae,
It goes into the right atrium
The right atrium contracts and the blood goes through the tricuspid valve and into the right ventricle
The right ventricle contracts and the blood is pushed out of the heart through the semi lunar or pulmonary valve and into the pulmonary artery
The pulmonary artery carries the blood to the lungs
The heart relaxes and the valves close to stop back flow of the blood
In the lungs, the blood becomes oxygenated, and begins it’s journey back to the heart.

13. The Left side of the heart
The heart is relaxed, and this allows blood to enter the left side of the heart from the pulmonary vein
It enters the left atrium
The left atrium contracts and pushes blood through the bicuspid valve and into the left ventricle
The left ventricle has a very strong muscular wall and contracts very strongly. This closes the bicuspid valve to prevent backflow, and pushes the blood through the aortic valve and into the aorta. This is the largest artery and splits taking the blood to different areas of the body
The heart contracts and the aortic valve closes, preventing back flow of the blood.

14. Terminology Heart rate (H.R.) Stroke Volume (S.V.) Cardiac Output
The amount of times the heart beats in a minute.
Usually measured in beats per minute (b.p.m.)
Stroke Volume (S.V.)
The amount of blood leaving the left ventricle in one beat.
Normally measure in mililitres
Cardiac Output
The amount of blood leaving the heart in one minute
Normally measured in litres/minute
Cardiac Output = Stroke Volume x Heart Rate

15. Task…
Finish off annotating and labelling the various parts of the heart: