The heart - structures and functions Flashcards
where is the right atrium and what does it do?
Receives deoxygenated blood from the body through the superior and inferior vena cavae. It then pumps the blood into the right ventricle.
Where is the right ventricle and what does it do?
Pumps deoxygenated blood into the pulmonary arteries, which carry it to the lungs for oxygenation.
Where is the left atrium and what does it do?
Receives oxygenated blood from the lungs through the pulmonary veins and pumps it into the left ventricle.
Where is the left ventricle and what does it do?
Pumps oxygenated blood into the aorta, which then distributes it throughout the body.
What is the semi-lunar valve and where is it?
Location: Between the right ventricle and the pulmonary artery.
Function: Prevents backflow of blood from the pulmonary arteries into the right ventricle after contraction.
What is the Tricuspid Valve and where is it?
Location: Between the right atrium and right ventricle.
Function: Prevents backflow of blood from the right ventricle into the right atrium when the ventricle contracts.
What is the Mitral valve and where is it?
Location: Between the left atrium and left ventricle.
Function: Prevents backflow of blood from the left ventricle into the left atrium during ventricular contraction.
what is the aortic valve and where is it?
Location: Between the left ventricle and the aorta.
Function: Prevents backflow of blood from the aorta into the left ventricle after contraction.
What is the superior vena cava?
Function: Carries deoxygenated blood from the upper half of the body (head, neck, and arms) to the right atrium.
What is the inferior vena cava?
Function: Carries deoxygenated blood from the lower half of the body (abdomen and legs) to the right atrium.
What are the pulmonary arteries?
Function: Carry deoxygenated blood from the right ventricle to the lungs for oxygenation.
What are the pulmonary veins?
Function: Carry oxygenated blood from the lungs to the left atrium.
What is the aorta?
Function: The largest artery in the body, it carries oxygenated blood from the left ventricle to the rest of the body.
What are the coronary arteries?
Function: Supply oxygen-rich blood to the heart muscle (myocardium). The left and right coronary arteries arise from the base of the aorta.
What are the coronary veins?
Function:
Return oxygen-rich blood from theheart muscle (myocardium), back to the heart. Smaller veins fuse to become a large THIN WALLED vein called:
CORONARY SINUS
This empties blood directly into the right atrium , where it will restart the cycle
What is the endocardium?
Location: The innermost layer, lining the chambers of the heart and covering the heart valves.
Function: Provides a smooth, frictionless surface for blood to flow through the heart chambers.
What is the myocardium?
Location: The middle layer, composed of cardiac muscle.
Function: The thick muscular layer responsible for contracting and pumping blood out of the heart.
What is the epicardium?
Location: The outer layer of the heart, also considered the visceral layer of the pericardium.
Function: Provides a protective layer and contains blood vessels that supply the heart muscle (coronary vessels).
What is the sinoatrial node (SA node)
Location: In the right atrium near the superior vena cava.
Function: Known as the “natural pacemaker” of the heart, it initiates electrical impulses that cause the heart to beat.
What is the atrioventricular node?
Location: At the junction of the atria and ventricles.
Function: Receives the electrical impulse from the SA node, delays it slightly to allow the atria to contract fully before the ventricles do.
What is the bundle of his?
Location: Passes from the AV node into the interventricular septum.
Function: Carries the electrical impulses from the AV node toward the ventricles.
What are the right and left branches?
Location: Extend from the Bundle of His down the sides of the interventricular septum.
Function: Conduct the electrical impulses to the right and left ventricles, respectively.
What are the purkinje fibres?
Location: Spread throughout the ventricular walls.
Function: Transmit the electrical impulse to the muscle cells of the ventricles, causing them to contract and pump blood to the lungs and body.
