CV 3

Question 1

What is blood pressure

Answer 1

Cardiac output x total peripheral resistance

Question 2

what is cardiac output

Answer 2

heart rate x stroke volume

Question 3

what is total peripheral resistance

Answer 3

resistance in blood flo win the arterioles

Question 4

the ability of pacemaker cells to spontaneously depolarize is determined by what

Answer 4

Pacemaker current (Ir) carried by slow Na influx through the HCN channel. It is an inward current, responsible for starting the depolarization phase.

Question 5

How does HCN work

Answer 5

cAMP binds to HCN channel, allowing Na+ influx

Question 6

Which hormones increase cAMP

Answer 6

NE - increase heart rate

Question 7

which hormones decrease cAMP

Answer 7

Acetylcholine - decrease heart rate

Question 8

what is stroke volume

Answer 8

end diastolic volume - end systolic volume

Question 9

what is preload

Answer 9

the degree to which ventricles are stretched. Represends ventricular end diastolic volume

Question 10

the more stretch of muscle fibers, the..

Answer 10

greater force in contraction

Question 11

contractility

Answer 11

the intrinsic ability of the heart to contract dependent on the amount of Ca and the binding between actin and myosin