The Human Heart Structure Flashcards
What is the heart made out of?
Cardiac muscle
What are the unique properties of the cardiac muscle?
Cardiac muscle is myogenic and does not fatigue
What is meant when it is said the cardiac muscle is “myogenic”?
This means the cardiac muscle can contract/relax without nervous/hormonal stimulation
What is meant when it is said the cardiac muscle “does not fatigue”?
This means as long as the cardiac muscle has a supply of oxygen and glucose, it will never fatigue
What are pulmonary vessels?
> Name all four of them
Blood vessels that connect the heart to the lungs, they include the pulmonary artery, pulmonary vein, aorta and vena cava
What is the function of the aorta, and which chamber is it connected to?
CHAMBER: The aorta is connected to the left ventricle
FUNCTION: Carries oxygenated blood to all parts of the body except the lungs
What is the function of the pulmonary artery, and which chamber is it connected to?
CHAMBER: The pulmonary artery is connected to the right ventricle
FUNCTION: Carries deoxygenated blood to the lungs for gas exchange
What is the function of the vena cava, and which chamber is it connected to?
FUNCTION: Brings deoxygenated blood back from the body - excluding lungs
CHAMBER: The vena cava is connected to the right atrium
What is the function of the pulmonary vein, and which chamber is is connected to?
FUNCTION: Bring oxygenated blood back from the lungs
CHAMBER: The pulmonary vein is connected to the left atrium
How does the heart receive oxygen for its own respiratory needs?
The heart is supplied with oxygen by the coronary arteries, which branch off the aorta shortly after it leaves the heart
Why doesn’t the heart use the oxygenated blood that passes through the left side of the heart?
The heart muscle has its own blood supply, ensuring it gets sufficient oxygen to meet its high respiratory needs
What happens when the coronary arteries become blocked?
A blockage in the coronary arteries can cause a myocardial infarction (heart attack), as part of the heart muscle is deprived of oxygen
Why does a blockage in the coronary arteries cause a heart attack?
Without oxygen, the affected heart muscle cells cannot respire aerobically, leading to cell death and potentially fatal heart failure
What can cause a blockage in the coronary arteries?
Blood clots or fatty deposits can narrow or block the coronary arteries , restricting blood flow
How do valves open and close?
Valves open when the pressure is higher, behind the valve and then proceed to close when pressure is higher, in front of the valve
What is the function of the septum?
The septum separates oxygenated and deoxygenated blood, ensuring oxygenated blood is not diluted by deoxygenated blood.
What does the septum allow to have maintained in the human heart?
The septum maintain a high concentration of oxygen in oxygenated blood to maintain concentration gradient which enables diffusion amongst respiring cells
What are the two main causes of a myocardial infarction?
The blockage of coronary arteries or coronary artery rupturing
