cardiovascular physiology

Question 1

how is blood pressure monitored?

Answer 1

baroreceptors

Question 2

what is the frank-starling mechanism?

Answer 2

if the ventricle stretches, it will contract with more force

ventricle stretches due to increase venous return which re-distributes blood to skeletal muscle = more forceful contraction

Question 3

what happens when things go wrong with coronary circulation?

Answer 3

myocardial infraction

AKA heart attacj

clogged coronary arteries = no blood passage = part of myocardium dies off and becomes weaker

Question 4

what is stroke volume?

Answer 4

the amount of blood per beat

Question 5

what is vasodilation?

Answer 5

opening of blood vessels

Question 6

what is the reason for nutrient exchange occuring in capillaries?

Answer 6

1) slow blood flow
2) thin vessel lining

Question 7

what is the septum?

Answer 7

the part that divides the heart into left and right halves

function: prevent sideways flow of blood

Question 8

why does the SV no longer increases after 60% intensity?

Answer 8

because the heart is beating so fast, diastolic has no time to fill back up with additional blood

Question 9

what are coronary arteries?

Answer 9

branch directly off the aorta, supplying blood to the myocardium

Question 10

what is diastolic blood pressure?

Answer 10

the pressure when the heart relaxes

when pressure bottoms out

Question 11

what is coronary cirulation?

Answer 11

blood vessels that supply blood to myocardium

Question 12

what is a hematocrit?

Answer 12

the number of RBC per volume of blood

Question 13

why may you have high blood pressure?

Answer 13

1) narrowed blood vessels
2) increased blood volume

Question 14

what is the difference of heart rate versus heart rhythm?

Answer 14

heart rate = the number fo times the heart beats per minute

heart rhythm = the pattern the heart beats at

Question 15

how does exercise change cardiac output?

Answer 15

increases because HR and SV increases

Question 16

what are b-adrenergic receptors?

Answer 16

receptors inside the myocardium that tells the heart to beat faster

Question 17

what is vasoconstriction?

Answer 17

narrowing of blood vessels

Question 18

what is the function of valves?

Answer 18

regulate blood flow between the chambers

Question 19

what are the three layers of the heart?

Answer 19

1) pericardium
2) myocardium (heart muscle layer)
3) endocardium

Question 20

how are blood vessels able to contrict?

Answer 20

the smooth muscle layer

Question 21

how does exercise change blood pressure?

Answer 21

it depends

1) muscles contractions = vasoconstriction = higher BP
2) valsalva maneuver = hold your breath=high systolic = ruptured blood vessels

Question 22

what is systolic blood pressure?

Answer 22

the pressure in the arteries when the heart contracts

Question 23

how much blood are in males and females?

Answer 23

Males = 5-6L

females = 4-5L

Question 24

how does the CNS control the heart rate?

Answer 24

1) medulla communicates with heart via
2) accelerator nerve to beat faster

OR

3) vagus nerve to beat slower

influenced by chemoreceptors and amgdyla (emotions)

Question 25

how are red blood cells removed?

Answer 25

by the spleen

Question 26

why does the heart require blood?

Answer 26

because it is a muscle too

Question 27

what is A-VO2?

Answer 27

how much O2 was extracted by muscles as blood passes through

Question 28

how does blood distribute durign exercise?

Answer 28

blood in internal organs shift over to the muscles

won’t be able to digest because blood is at skeletal muscles

Question 29

how mant chambers are in the heart?

Answer 29

4 chambers

Question 30

what is cardiac output?

Answer 30

the amount of bloof pumped out of left ventricle per minute

Question 31

how does exercise affect stroke volume?

Answer 31

stroke volume rises to 110-130mL due to the fraank starling mechanism

Question 32

how do we ensure blood gets back to the heart?

Answer 32

1) valves in veins
2) muscle pump
3) peripheral vasoconstriction
4) respiratory pump

**ONE AT A TIME**

Question 33

why is an ECG while resting not sufficient when checking for myocardial infraction?

Answer 33

at rest, the heart looks normal.. once the heart is under stress, that is where we will see not enough blood gettingthrough to supply the working myocardium (depressed ST segment)

Question 34

what is an ejection fraction (EF)?

Answer 34

the percentage of left ventricle volume ejected each beat

harder you work, higher EF % goes

NEVER 100% .. around 60%

Question 35

what is te benefit of being “psyched up” during your workout?

Answer 35

increases HR + circulates processes faster = better workout

Question 36

how does A-VO2 change during exercise?

Answer 36

it increases during exercise

• increase O2/CO2 concentration gradient, results in easier diffusion