Module 9 ML-1

Question 1

What is cardiac output

Answer 1

the volume of blood coming out of each ventricle per unit time

Question 2

What is the average CO

Answer 2

5L/min

Question 3

Cardiac output can be influenced by whay

Answer 3

both divisions of the autonomic nervous system

Question 4

How does the parasympatheic affect cardiac output?

Answer 4

Ach to muscarinic recpetors within the atria ( SA, AV, and Atrial contractile cells

Question 5

How does the sumpathetic affect the cardiac output

Answer 5

NE to beta 1 within the whole heart
Epi to beta 1 within the whole heart

Question 6

In a resting person what is the state of the para and symp

Answer 6

para: on
symp: off

Question 7

If you increase physical activity what happens

Answer 7

increased symp output
decreased para output

Question 8

What are the intrinisc rates of the SA node, AV node, his/purkinje

Answer 8

SA: 100
AV: 70
His/purkinje: 30

Question 9

What are the major affects influencing heart rate

Answer 9

-epi onto beta 1 increased the symp NS which increases HR
-Ach onto alpha 1 will increase the para and decrease heartrate
-ALL EFFECTS EXERTED ONTO THE SA NODE

Question 10

Pacemaker potential in SA node celss in slowed and quickened by what

Answer 10

slowed: para
quickened: symp

Question 11

Chronotropic effect

Answer 11

factors that alter the heart rate

Question 12

How does the symp make depol go faster

Answer 12

-no change in potassium current
-increased funny sodium current
-increased T type calcium current

Question 13

How does para make depol go slower

Answer 13

-increase of voltage gated potassium current
-decreased funny sodium current
-decreased t type calcium current

Question 14

True/False: upstroke of AP is also affected by symp and para

Answer 14

true

Question 15

Dromotropic effects

Answer 15

conduction velocity changes

Question 16

Symp ion channel change makes upstrok faster

Answer 16

increase in L type calcium current

Question 17

Para ion channel change makes upstroke slower

Answer 17

decrease of L type calcium current

Question 18

If you have an increased venous return what occurs

Answer 18

higher ECV and imporved overlap of actin
-heartbeat will be stronger to eject all the blood

Question 19

What does increased EDV cause

Answer 19

increased length of cells, increased tension and increased SV

Question 20

EDV

Answer 20

how much we fill

Question 21

What is an intrinisc mechamisn of regulating SV

Answer 21

if ventricle fills to a large volume than the next beat is stronger to eject the extra blood

Question 22

What is the frank starling mechanism

Answer 22

contraction force and stroke volume change in response to venous return

Question 23

Example of frank starling

Answer 23

instead of noraml 135 mL EDV is it 165mL so Sv has to go up 30 to get 65 mL again

Question 24

Implications of frank starling

Answer 24

-prevents a rise in ESV( prevents clotting)
-matching of LV and RV output; (if venous reutn increased on either side, CO increased)
-prevention of rise in venous pressure