Where is the heart found?
In the thorax, lying in the mediastinum.
What is the mediastinum?
The space between two pleural membranes.
What is the name for the protective sack surrounding the heart?
Pericardium
What makes up the pericardium?
Tough fibrous pericardium (outer layer)
Inner serous membrane (parietal pericardium)
How many layers make up the heart wall?
3
What layers make up the heart wall?
Epicardium (outer epithelial layer)
Myocardium (cardiac muscle)
Endocardium (epithelial layer lining inside of the heart)
What does the right side carry?
Deoxygenated blood from the systemic circulation and passes it to the pulmonary circulation.
What does the left side of the heart do?
Carries oxygenated blood from the pulmonary circulation and passes it into the systemic circulation.
How many chambers of the heart are there?
4
Which ventricle is thicker?
The left ventricle is much thicker than the right.
Why is the left ventricle thicker?
As it’s pumping the blood all around the body.
Where do the atria receive blood from?
Veins
Where does the right atrium receive blood from?
Vena cava
Where does the left atrium receive blood from?
The pulmonary vein
Where do the ventricles pump blood to?
Arteries
Where does the right ventricle pump blood into?
The pulmonary artery
Where does the left ventricle pump blood into?
The aorta
What is the biggest blood vessel?
Aorta
What do valves do?
Keep blood moving in the correct direction and prevent backflow.
What are the atrio-ventricular valves (AV valves)?
Tricuspid
Mitral
What muscles are valves attached to?
Papillary muscles
What happens during diastole?
Relaxation
Atria and ventricles are relaxed, blood enters the atria from the veins
What happens during atrial systole?
The atria contract and the AV valves open
Blood moves into the ventricles
What happens during ventricular systole?
The ventricles contract, the AV valves close and the semi-lunar valves open.
Blood flows into the arteries
