Cardiac Cycle + BP

Question 1

heart beat

Answer 1

• aka cardiac cycle

- consists of contraction + relaxation of heart chambers

Question 2

avg heart rate

Answer 2

70 beats per minute

Question 3

length of heart beat

Answer 3

~ 0.85 seconds

Question 4

systole

Answer 4

contraction of heart chambers

Question 5

diastole

Answer 5

relaxation of heart chambers

Question 6

why do atria contract for shorter time than ventricles

Answer 6

pump blood shorter distance (to ventricles rather than to entire body)

Question 7

heart sounds

Answer 7

lub - dub

Question 8

lub

Answer 8

atrioventricular valves (tricuspid + bicuspid) close

Question 9

dub

Answer 9

semilunar (aortic + pulmonary) valves close

Question 10

BP cuff official name

Answer 10

sphygmomanometer

Question 11

how sphygmomanometer works

Answer 11

• measures pressure required to stop blood flow through brachial artery
• squeeze bulb inflates bladder (held over artery via cuff)
• once inflated, turn valve to slowly empty bladder and let blood flow again
• use stethoscope to hear first and last blood sounds displayed

Question 12

second phase of cardiac cycle

Answer 12

atria in diastole, ventricles in systole (~0.30 sec)

Question 13

third phase of cardiac cycle

Answer 13

all chambers in diastole (~0.45 sec)

Question 14

systolic pressure

Answer 14

pressure in arteries during ventricular systole

Question 15

diastolic pressure

Answer 15

pressure in arteries during ventricular diastole

Question 16

blood pressure in veins

Answer 16

= 0
blood returns to heart because veins are stretchy, internal valves prevent back flow, and muscles contract in limbs and chest