Lesson 6 - Cardiovascular Dynamics and Physiolgy

Question 1

blood flows through the body in what kind of system?

Answer 1

a closed circulation system

Question 2

what can impact the rate of blood flow? (2)

Answer 2

the physical properties of blood and of blood vessels

Question 3

what other factors can influence blood flow? (2)

Answer 3

• blood pressure
• peripheral resistance

Question 4

blood flow equation

Answer 4

deltaQ: amount of blood flowing through the area
P: blood pressure; force of blood against vessels
n: ‘thickness’ of blood
r: radius of vessel
l: length of vessel blood travels through

Question 5

the heart can only pump blood that is held…

Answer 5

within its ventricles

Question 6

diastole (2)

Answer 6

relaxation, heart chamber is able to fill with blood

Question 7

end diastolic volume (EDV)

Answer 7

blood volume in ventricles before contraction

Question 8

systole (2)

Answer 8

contraction, chamber pushes blood out

Question 9

end systolic volume (ESV)

Answer 9

blood volume remaining after ventricular

Question 10

stroke volume (SV)

Answer 10

amount of blood pumped per contraction

Question 11

stroke volume equation

Answer 11

EDV-ESV
end-diastolic - end-systolic

Question 12

cardiac output

Answer 12

amount of blood pumped by each ventricle

Question 13

cardiac output equation

Answer 13

SV x heart rate (in bpm)

Question 14

as you increase the radius of blood vessels, the peripheral resistance of blood flow _____

Answer 14

decreases

Question 15

radius of blood flow is _____ proportional to peripheral resistance

Answer 15

exponentially

Question 16

how does the body regulate blood vessel radius?

Answer 16

through contraction or relaxation of the smooth muscles in those vessels, controlled by the ANS

Question 17

what is an advantage of slowing blood flow at capillaries?

Answer 17

to increase the time for nutrient/waste exchange

Question 18

as blood viscosity increases, blood flow _____

Answer 18

decreases

Question 19

the relationship between viscosity and blow flow is…

Answer 19

negative exponential

Question 20

ways in which blood viscosity increases (2)

Answer 20

• number of blood cells increases like polycythemia
• amount of plasma decreases like through dehydration

Question 21

as vessel length increases, blood flow _____

Answer 21

decreases

Question 22

vessel length is _____ proportional to blood flow

Answer 22

inversely/negative exponential (?)

Question 23

why does resistance increase with vessel length?

Answer 23

blood flowing through a long vessel with interact with the walls for a greater period of time, producing more friction

Question 24

it is much easier for the body to control blood flow through what? Over what?

Answer 24

radius of blood vessels vs. trying to destroy and shorten blood vessels

Question 25

as pressure increases, flow _____

Answer 25

increases

Question 26

pressure is _____ proportional to blood flow

Answer 26

directly (linear relationship)

Question 27

how can the cardiovascular system increase blood flow?

Answer 27

causing an increase in blood pressure through increasing the force of cardiac muscle contraction

Question 28

what can high blood pressure to do vessels?

Answer 28

can damage them if they are not used to higher pressures, possibly bursting

Question 29

as the right radius increases, peripheral resistance _____ and blood flow _____

Answer 29

decreases, increases- right radius is the aorta (?)

Question 30

how does pressure remain the same even as the radius changes?

Answer 30

the increase in blood pressure by the heart when vessels dilate balances out the decrease in resistance

Question 31

as stroke volume increases, pump rate _____

Answer 31

decreases

Question 32

why does pump rate decrease with increased stroke volume?

Answer 32

the preload (amount of blood filling the ventricles) increases, it takes more time to push out that volume

Question 33

increases in stroke volume are balanced by...

Answer 33

decreases in heart rate to keep cardiac output the same

Question 34

why might an athlete's heart rate be lower than normal?

Answer 34

their heart has a higher stroke volume and does not require as high of a heart rate to push the same amount of blood, they also have a lower afterload

Question 35

what does an aortic valve stenosis do to the heart?

Answer 35

increases afterload, aka the resistance to blood flow out of the heart

Question 36

what does the heart have to do to overcome a higher afterload?

Answer 36

the heart has to contract harder to create more pressure to force blood out

Question 37

someone with an aortic valve stenosis will have thicker _____

Answer 37

myocardium, the heart has to pump harder

Question 38

what is the mechanism the heart uses to compensate for an aortic valve stenosis?(2)

Answer 38

increase contractility by sympathetic stimulation, or norepinephrine/epinephrine release

Question 39

the heart has _____ and _____

Answer 39

automaticity and rhythmicity

Question 40

what does it mean for the heart to have automaticity and rhythmicity?

Answer 40

it can spontaneously depolarize in a regular and continuous manner to cause heart contractions

Question 41

contractions of the heart can be influenced by what two things?

Answer 41

parasympathetic or vagal stimulation, and sympathetic stimulation

Question 42

what can over stimulation of the parasympathetic system cause? how can it rescue itself?

Answer 42

- the heart can stop beating !! - but it can 'restart' by means of vagal escape

Question 43

vagal escape

Answer 43

caused by sympathetic reflexed or rhythm initiation by Purkinje fibers

Question 44

since the heart can be influenced by both the sympathetic and parasympathetic systems...(3)...can affect heart rate/contractions.

Answer 44

- direct stimulation of the systems can change heart rate - chemicals that affect the systems also affect the heart - ions can also affect heart contractions

Question 45

what ions can impact heart contraction? (3)

Answer 45

Ca2+, K+, and Na+

Question 46

What data is being shown by this graph?

Answer 46

vessel radius on pump activity - right radius represents the aorta

Question 47

What is being displayed in this data?

Answer 47

blood vessel radius on pump activity (?)

Question 48

what does this graph show?

Answer 48

flow rate dependent on pressure

Question 49

what does this data show?

Answer 49

flow rate dependent on pressure

Question 50

what does this graph show?

Answer 50

flow rate vs. length of vessels

Question 51

what does this data show?

Answer 51

blood vessel length on blood flow rate

Question 52

what does this graph show?

Answer 52

flow rate vs. blood viscosity

Question 53

what does this data show?

Answer 53

blood flow vs. blood viscosity

Question 54

what does this graph show?

Answer 54

flow rate vs. vessels radius

Question 55

what does this graph show?

Answer 55

blood vessel radius vs. blood flow