function of the heart C17

Question 1

cardiac cycle

Answer 1

the events of one heartbeat

• atrial systole
• ventricular systole
• diastole

Question 2

systole

Answer 2

• contraction of the myocardium

- forces blood out

Question 3

diastole

Answer 3

• relaxation of the myocardium

- lets the blood refill

Question 4

vagomimetic

Answer 4

mimics vagal stimulation

Question 5

vagolytic

Answer 5

blocks the effects of the vagus nerve

Question 6

cardiac output

Answer 6

the amount of blood pumped by the ventricle in 1 minute

normal 5L/min

Question 7

venous return

Answer 7

the rate of blood flow back to the heart

Question 8

cardiac output equation

Answer 8

cardiac output = heart rate x stroke volume

Question 9

stroke volume

Answer 9

the amount of blood pumped by the ventricle per beat

normal 60-80mL/beat

Question 10

starling’s law of the heart

Answer 10

the relationship of myocardial stretch to myocardial contractile force
(allows the heart to pump out the same amount it received)
-changes stroke volume

Question 11

inotropic effect

Answer 11

strengthen the force of myocardial contraction without stretching the myocardial fibers - positive inotropic effect
failing heart - negative inotropic effect

Question 12

ejection fraction

Answer 12

the % of the EDV that is pumped
regular - 67
healthy - up to 90 w exercise
failing heart - low as 30

Question 13

cardiac reserve

Answer 13

the capacity to to increase cardiac output above the resting cardiac output