Heart Structure Flashcards
What is the tick muscular layer in the walls of the heart called ?
Cardiac muscle
What is a property of the cardiac muscle ?
It is myogenic
-so it can relax and contract without nervous or hormonal stimulation
What is another property of the cardiac muscle ?
It does not fatigue
- as long as it has a supply of oxygen and glucose
What is the function of the cardiac muscle ?
Supply the cardiac muscle with a constant supply of oxygenated blood
Where are the coronary arteries located?
They branch off from the aorta
What is a heart attack otherwise known as ?
Myocardial infraction
What will happen if the coronary arteries become blocked ?
The cardiac muscle will not receive any oxygen so it will not be able to respire and the cells will die
Features of the atria
Thinner muscular walls
-as they do not need to contract as hard as they are only pumping blood to the ventricles
Elastic walls to stretch and increase in volume when the blood enters
Features of the ventricles
Thicker muscular walls to enable bigger contraction
-this creates a high blood pressure which allows the ventricles to pump blood for longer distances
E.g lungs and the rest of the body
Why is the right ventricle thinner than the left ?
Because it pumps blood to the lungs which needs to be at a lower pressure to prevent damage to capillaries in the lungs and so blood flows slowly for gas exchange
Why is the left ventricle have a thicker wall than the right ?
Because it pumps blood around the body.
This blood needs to be at a higher pressure so larger contractions are needed to ensure blood reachers all the cells in the body
Function of vena cava
Carries deoxygenated blood from the body to the right atrium
Pulmonary vein
Carries oxygenated blood from the lungs to the left atrium
Pulmonary artery
Carries deoxygenated blood from the right ventricle ro the lungs
Aorta
Carries oxygenated blood from the left ventricle to the rest of the body
