CVS - Exercise & Recovery

Question 1

where is the cardiac control centre located

Answer 1

medulla oblongata

Question 2

what is the cardiac control centres primary responsibility

Answer 2

regulating the heart (heart rate)

Question 3

what nervous system is cardiac control centre controlled by & what this means

Answer 3

• automatic nervous system
• under involuntary control

Question 4

what are the 3 types of neural control

Answer 4

• chemo-receptors
• baro-receptors
• proprio-receptors

Question 5

what do chemo-receptors detect (2)

Answer 5

• increase in CO2
• decrease in blood pH (increased acidity - lactic acid)

Question 6

what do baro-receptors detect

Answer 6

increase in blood pressure

Question 7

what do proprio-receptors detect

Answer 7

increase in muscle movement

Question 8

what is the type of hormonal control

Answer 8

adrenaline

Question 9

what does adrenaline do

Answer 9

released before exercise to increase heart rate (fight or flight)

Question 10

what is the type of intrinsic control

Answer 10

thermo-receptors

Question 11

what do thermo-receptors detect

Answer 11

increase in body/muscle temperature - result of onset of exercise

Question 12

where are messages from receptors sent to

Answer 12

medulla oblongata

Question 13

where do messaged from medulla oblongata go to

Answer 13

cardiac control centre

Question 14

what nervous system does messages from cardiac control centre go down + what as

Answer 14

• sympathetic nervous system
• electronic impulse

Question 15

(CCC) where does message down sympathetic nervous system go to

Answer 15

SA node

Question 16

what does message to SA node do + name of system

Answer 16

• increases impulses from SA node to increase heart rate
• conduction system

Question 17

what does the parasympathetic nervous system do + why

Answer 17

• decreases heart rate
• cardiac control centre stops receiving messages from receptors

Question 18

3 factors affecting cardiac control centre

Answer 18

• neural control
• hormonal control
• intrinsic control

Question 19

what does adrenaline do to SA node

Answer 19

directly stimulates it to increase heart rate & stroke volume

Question 20

where is the vasomotor control centre found

Answer 20

medulla oblongata

Question 21

what does the vasomotor control centre control

Answer 21

vascular shunt

Question 22

what is vascular shunt

Answer 22

redistribution of blood around the body when starting to exercise

Question 23

which nervous system does the vasomotor control centre stimulate & what does this do

Answer 23

• sympathetic nervous system
• vasodilator or vasoconstrict pre-capillary sphincters & arterioles supplying blood to muscles & organs

Question 24

what does vasodilation of pre capillary sphincters do

Answer 24

more blood to working muscles when exercising

Question 25

what does vasodilation of arterioles do

Answer 25

increase blood flow to working muscles when exercising

Question 26

what is vasodilation of pre-capillary sphincters

Answer 26

opening of them

Question 27

what is vasoconstriction of pre-capillary sphincters

Answer 27

closure of them

Question 28

what does vasoconstriction of pre-capillary sphincters do

Answer 28

decrease blood flow to non vital organs when exercising

Question 29

what does vasoconstriction of pre-capillary sphincters do

Answer 29

decrease blood flow to non vital organs when exercising

Question 30

where does vasomotor control centre receive information from (5)

Answer 30

• chemo-receptors
• baro-receptors
• proprio-receptors
• adrenaline
• thermo-receptors

Question 31

what are pre-capillary sphincters

Answer 31

rings of smooth muscle at openings of capillaries

Question 32

2 ways in which blood is redistributed during vascular shunt

Answer 32

vasodilation & vasoconstriction of:
- pre-capillary sphincters
- arterioles

Question 33

where is vasomotor control centre & where does it receive message from

Answer 33

• medulla oblongata
• receptors

Question 34

where is message from vasomotor control centre sent

Answer 34

doen sympathetic nervous system

Question 35

(VCC) where does message down sympathetic nervous system go to & what does this do

Answer 35

• arterioles & pre-capillary sphincters leading to working muscles - vasodilate - more blood can go to WM when exercise
• arterioles & pre-capillary sphincters leading to non-vital organs - vastoconstrict - less blood to non-vital organs

Question 36

5 mechanisms of venous return

Answer 36

• pocket valves
• muscle pump
• respiratory pump
• smooth muscle
• gravity

Question 37

what do pocket valves d0 (2)

Answer 37

• valves in vein
• prevent back flow of blood & direct blood flow back to heart

Question 38

what does muscle pump do (2)

Answer 38

• vein between muscle
• muscle contract & relax helps push blood through vein back to heart

Question 39

what does respiratory pump do (4)

Answer 39

• exercise - breathing = deeper & faster
• causes pressure change in thorax & abdomen
• increases pressure in abdomen - large veins in that area squeezed
• this forced blood back to heart

Question 40

what does smooth muscle do (venous return mechanism) (2)

Answer 40

• contraction & relaxation of smooth muscle within middle layer of veins walls
• pushes blood through veins towards heart

Question 41

what does gravity do (venous return mechanism)

Answer 41

blood from above heart aided by gravity to help blood flow back to heart

Question 42

what is starlings law

Answer 42

increase in venous return leads to increase in stroke volume when exercise

Question 43

how does starlings law work (3)

Answer 43

• heart is muscle - when warms up = more elastic
• means can contain more blood & contract with more force
• means stroke volume increases when start to exercise