Circualtion Of Heart Flashcards
What does the atria do
Receives blood returning to the heart
What does the vena cava do?
Returns DEOXYGENATED blood to the rift atrium
What does the pulmonary vein do?
Gives OXYGENATED blood to the left atrium
What does the right ventricle do?
Pumps DEOXYGENATED blood through pulmonary artery to the lungs
What does left ventricle do?
Pumps OXYGENATED blood through aorta
What does the septum do?
Separates two sides
How to calculate cardiac output
Heart rate X stroke volume
What happens during diastole ? ( 3)
- Muscles relax
- High pressure closes SL valves
- Atria fills with blood from vena cava and pulmonary vein & some flow to ventricles
What happens in systole?
- Atria contract
- remainder of blood transfer through AV valves into ventricles
- ventricular systole closes AV valves to allow blood to transfer through aorta and pulmonary artery
What is the average length of a cardiac cycle?
0.8 seconds
What are heart murmurs and what causes them?
Caused by abnormal patterns I.e valves fail to open or close properly
When is there high and low pressure ?
Diastole - low pressure
Systole - high pressure
What does the SAN do?
Sets the rate at which cardiac muscles contract
Describe route of electrical impulses
- from SAN (top of atria) pass to AVN (bottom)
- AVN go through septum to muscles in ventricles
- results in muscle contractions
What is an electrocardiogram (3)
- shows electrical pulses from heart beat
- can identify problems with the heart I.e MI
- place electrodes on surface of body
