4.3 Physiology of the Cardiovascular System Part 2 Flashcards
What is heartbeat also known as?
cardiac cycle
What are the three general phases of the cardiac cycle?
- atria contract while ventricles relax (0.15s)
- ventricles contract while atria relax (0.30s)
- all chambers relax (0.40s)
What are the sounds of the heartbeat?
lub dub
What is the first lub?
when the atrioventricular valves close
What are the atrioventricular valves?
bicuspid
tricuspid
What is the dub sound?
when the semilunar valves close
What does systolic pressure result from?
blood being forced into the arteries during ventricular systole
What is diastolic pressure?
pressure in the arteries during ventricular diastole
What is the medical device that measures blood pressure?
sphygomanometer
What does blood pressure measure?
the amount of pressure required to stop the flow of blood through an artery
What is the normal artery that blood pressure is taken at?
brachial artery
What is used to squeeze are into the bladder?
bulb
What is placed over the artery to measure blood pressure?
the cuff
What displays the pressure and in what unit?
manometer/ mmHg
What is the normal reading for blood pressure?
120/80
What is the numerator and what is the denominator in blood pressure readings?
systolic/diastolic
What happens to the difference in pressure between systolic and diastolic when blood reaches the arterioles?
the difference will diminish
What are the factors that enable blood to return to the heart in veins that have low pressure?
- low resistance in venous walls
- internal valves in veins prevents backflow
- muscular contraction assists flow rate in veins
What maintains the intrinsic rhythmic abilities of the heart?
electrical impulses
What systems help regulate heart rate?
nervous system
endocrine system
