The cardiovascular system

Question 1

Sally will always aim balls past vicky

Answer 1

Sinoatrial node generates electrical impulses
causing a wave of excitation
These impulses go into atrial walls and contract, forcing blood into the ventricles = Atrial stole
Atrioventricular node
Impulses go to the bundle of his
Into the purkinje fibres
Which force the ventricles to contract and push blood out of the heart

Question 2

Why shouldn’t you eat before a competition

Answer 2

Blood flow will increase to the stomach and intestines instead of working muscles, increasing the effect of fatigue

Question 3

When is the latest you should eat before a competition

Answer 3

An hour

Question 4

What 3 things have a constant blood supply

Answer 4

Brain
Heart
Cardiac muscle

Question 5

How to control blood flow

Answer 5

Vasoconstriction and vasodilation

Question 6

What controls vasoconstriction and vasodilation

Answer 6

vasomotor centre

Question 7

Where is the vasomotor located

Answer 7

Medulla oblongata

Question 8

What 3 things is the vasomotor responsible for

Answer 8

Regulation of heart rate, blood pressure and redistribution of blood

Question 9

What is the process of vascular shunting

Answer 9

An increase of CO2 and lactic acid is detected by chemoreceptors
Chemoreceptors stimulate the vasomotor
The vasomotor signals for a redistribution of blood flow
Vasodilation and vasoconstriction occur and the pre-capillary sphincter adjust blood flow into the capillaries

Question 10

What is the A-V02 difference

Answer 10

The difference between the volume of oxygen the arteries and veins carry

Question 11

At rest the A-V02 diff is high/low?
Why

Answer 11

Low- the muscles don’t need as much blood

Question 12

During exercise A-V02 diff is high/low?
Why

Answer 12

High- more oxygen is required by muscles

Question 13

How does A-V02 diff affect gaseous exchange

Answer 13

It increases

Question 14

Explain the Bohr shift

Answer 14

During exercise CO2 and lactic acid increases and need to be removed
Working muscles need more oxygen to aerobically respire

Question 15

why is the redistribution of blood important?

Answer 15

ensure more blood goes to the skin to regulate body temperature through sweating and evaporation

ensure the heart has an increase of oxygen to beat faster

increase the supply of oxygen to the working muscles for aerobic respiration

remove waste products like lactic acid and CO2

Question 16

what does the oxyhaemoglobin dissacoiation curve represent

Answer 16

the saturation of O2 in haemoglobin against the partial pressure of O2 in different areas of the body

Question 17

will haemoglobin be more saturated at tissues or at the lungs?
why?

Answer 17

lungs as the lungs have a higher partial pressure of O2 and don’t need haemoglobin to release oxygen
tissues need oxyhaemoglobin to release oxygen so they can aerobically respire

Question 18

what is haemoglobin
what is oxyhaemoglobin
what is plasma
what is myoglobin

Answer 18

an oxygen binding protein found in the blood
when oxygen is combined with haemoglobin
liquid part of blood
an oxygen binding protein found in the muscle tissue

Question 19

during exercise myoglobin has a higher affinity for oxygen than haemoglobin
why

Answer 19

muscle tissue need to aerobically respire more and faster and therefore requires more oxygen from haemoglobin

Question 20

explain
baroreceptors
chemoreceptors
propriorecpetors

Answer 20

baro- detect an increase in blood pressure
chemo- detect an increase of acidity in the blood due to an increase in CO2
proprio- detect an increase in muscle movement

Question 21

cardiac output= A x B
what is A and B

Answer 21

heart rate
stroke volume

Question 22

what is stroke volume

Answer 22

the volume of blood pumped out by the heart per contraction

Question 23

how to calculate max heart rate

Answer 23

220-age

Question 24

what is starlings law

Answer 24

increased venous return —-> greater diastolic filling of the heart —-> cardiac muscle stretches more —-> more force of contraction —-> increased ejection fraction

increase in venous return = increased stroke volume

Question 25

the relationship between stroke volume and exercise

Answer 25

as exercise increases, stroke volume increases by 40-60% then it plateaus as the ventricles have less time to fill up

Question 26

how does having more elastic cardiac fibres effect stroke volume

Answer 26

the greater they stretch the greater force of contraction and bigger ejection rate, increasing stroke volume

Question 27

what does the sympathetic nervous system do to the heart

Answer 27

stimulates heart rate

Question 28

what does the parasympathetic nervous system do to the heart

Answer 28

returns it to resting heart rate

Question 29

where are the para and sympathetic nervous system

Answer 29

cardiac control centre in the medulla oblongata

Question 30

the sympathetic system stimulates which receptors

Answer 30

chemo and proprio

Question 31

the parasympathetic system stimulates which receptors

Answer 31

baro

Question 32

Just before taking part in exercise, the sympathetic nervous system increases activity which causes the a_______ g_____ to release ______________ into the blood stream. This causes an ___________ ______ in the heart rate. As it stimulates the SAN to increase/decrease s______ and force of ______________ to increase/decrease cardiac output

Answer 32

adrenal glands adrenaline anticipatory rise increase speed contraction increase

Question 33

what is a stroke

Answer 33

when the brain is deprived of oxygen causing damage and death to the cells

Question 34

ischaemic stroke

Answer 34

a blood clot stops the bloody supply to the brain

Question 35

haemorrhagic

Answer 35

weakened blood vessels supplying blood to the brain burst and blood leak into the brain

Question 36

describe cardiovascular drift

Answer 36

occurs during prolonged exercise ----> heart rate increases ----> stroke rate decreases ---> because fluid is lost as sweat ----> reduced plasma volume -----> reduced venous return -----> increased cardiac output to cool the body

Question 37

how does cardiac muscle hypertrophy effect heart rate

Answer 37

cardiac muscles becomes bigger and stronger so increases stroke volume and decreases heart rate

Question 38

what is bradycardia how does it effect oxygen delivery

Answer 38

decreased resting heart rate (60 bpm) less oxygen is needed to carry out contractions of the heart so more oxygen can be delivered to muscle tissues

Question 39

what is coronary heart disease what is the process called what is atherona causes

Answer 39

when coronary aerteries, which supply oxygenated blood to the heart, become blocked or narrowed by fatty deposits. atherosclerosis fatty deposits high cholesterol, high blood pressure, lack of exercise, smoking

Question 40

what is blood pressure what can high bp lead to

Answer 40

the force exerted by the blood against the blood vessel walls heart attack, stroke, kidney failure, heart failure, dementia

Question 41

what is systolic pressure what is diastolic pressure

Answer 41

systolic- high pressure in the arteries when the ventricle contracts diastolic- low pressure in the arteries when the ventricles relax

Question 42

role of: veins arteries capillaries

Answer 42

veins- transport deoxygenated blood to the heart arteries- transport oxygenated blood to the rest of the body capillaries- allow for the exchange of substances

Question 43

describe the structure of veins: muscle tissue pressure outer walls lumen size

Answer 43

thin low elastic wider

Question 44

describe the structure of arteries: muscle tissue pressure outer walls lumen size

Answer 44

thick high elastic smaller

Question 45

describe structure of capillaries

Answer 45

only wider enough for 1 red blood cell at a time slow blood flow

Question 46

what is venous return

Answer 46

the return of blood to the right side of the heart via the vena cava

Question 47

state and describe the 5 active mechanisms used to aid venous return

Answer 47

the skeletal muscle pump- when muscles contract and relax they change shape. The muscles then press on nearby veins and cause a pumping effect to squeeze the blood towards the heart the respiratory pump- when muscles contract and relax during breathing in and out changes occur in the chest and abdominals. these compress on nearby veins and assist the blood flow pocket valves- prevent back flow of the blood and close when all the blood has travelled through thin layer of smooth muscle in the walls of veins help squeeze blood back towards the heart gravity- helps blood from the upper body to return to the heart

Question 48

how does systolic pressure effect venous return

Answer 48

sp increases = vr increases sp decreases = vr decreases

Question 49

how to calculate total peripheral vascular resistance

Answer 49

venous pressure - right atrial pressure / venous vascular resistance

Question 50

how does right atrial pressure effect venous return

Answer 50

right atrial pressure increases = venous return decreases right atrial pressure decreases = venous return increases

Question 51

describe the transport of oxygen to working muscles

Answer 51

oxygen binds to haemoglobin to form oxyhaemoglobin transported via plasma to the working muscles there is a low partial pressure of oxygen in the muscles so oxygen is released and diffuses into the muscles to form myoglobin oxygen is used to aerobically respire in the mitochondria and release energy

Question 52

what is vascular shunting

Answer 52

the redistribution of cardiac output (blood flow to areas where it is most needed)

Question 53

what is the pre-capillary sphincter what happens when it contracts what happens when it relaxes

Answer 53

tiny rings of muscles located at the openings of capillaries contracts= vasoconstriction relaxes= vasodilation