1.1b Cardiovascular system Flashcards by Mrs Suter

what does the cardiovascular system refer to?

heart
blood
blood vessels

How well did you know this?

Not at all

Perfectly

What is the pulmonary circuit?

Circulation of blood through the pulmonary arteries to lungs and pulmonary veins back to the heart.

How well did you know this?

Not at all

Perfectly

What is the systemic circuit?

Circulation of blood through the aorta to the body and vena cavae back to the heart.

How well did you know this?

Not at all

Perfectly

What is the pathway of oxygenated blood once it leaves the lungs?

pulmonary vein
left atrium
bicuspid/mitral valve
left ventricle
semilunar valve
aorta
body

How well did you know this?

Not at all

Perfectly

What is the pathway of deoxygenated blood once it after it leaves the rest of the body?

vena cava
right atrium
tricuspid valve
right ventricle
semilunar valve
pulmonary artery
lungs

How well did you know this?

Not at all

Perfectly

Describe the left side of the cardiac muscle compared to right and explain why.

left side has a thicker muscular wall

allows it to forcefully contract to circulate oxygenated blood through the systemic system to muscles and organs

How well did you know this?

Not at all

Perfectly

How many chambers does the heart have and what are they?

4
right atrium
left atrium
right ventricle
left ventricle

How well did you know this?

Not at all

Perfectly

How many valves does the heart have and what are they?

4
tricuspid valve
bicuspid valve
pulmonary semilunar valve
aortic semilunar valve

How well did you know this?

Not at all

Perfectly

How many blood vessels attach to the heart and what are they?

4
vena cava
pulmonary artery
pulmonary vein
aorta

How well did you know this?

Not at all

Perfectly

How many features of the conduction system are there and what are they?

4
SA node
AV node
bundles of His
Purkinje fibre

How well did you know this?

Not at all

Perfectly

What is the conduction system?

A specialist bundle of tissues that transmit the electrical pulse through the heart causing a coordinated contraction.

How well did you know this?

Not at all

Perfectly

Where is the SA node and what does it do?

wall of right atrium

sends an impulse across both atria causing atrial systole

How well did you know this?

Not at all

Perfectly

Where is the AV node and what does it do?

In the middle wall of the heart between atria and ventricles.
Receives impulse from SA node, delays it for a moment to allow for atrial systole to finish and sends it down the bundles of His.

How well did you know this?

Not at all

Perfectly

Where is the bundles of His and what does it do?

In middle wall of the heart.

Transmit impulse to the bottom of the right and left side of the heart.

How well did you know this?

Not at all

Perfectly

Where is the Purkinje fibres and what does it do?

In walls of ventricles.

Cause impulse to penetrate into ventricle wall causing ventricular systole.

How well did you know this?

Not at all

Perfectly

Define the cardiac cycle.

All the events associated with the flow of blood through the heart during one complete heartbeat.

atrial diastole
atrial systole
ventricular diastole
ventricular systole

How well did you know this?

Not at all

Perfectly

What controls the cardiac cycle?

Conduction system –> to produce highly coordinated contractions of the heart

How well did you know this?

Not at all

Perfectly

Define systole.

It is the heart working
The contraction phase of the heart chamber when it is pumping blood out.
1. atrial systole - blood pumped into ventricles
2. ventricular systole - blood pumped into pulmonary artery and aorta

How well did you know this?

Not at all

Perfectly

Define diastole.

It is the heart relaxing
The relaxation phase of the heart chamber when it is receiving blood.
1. atrial diastole - blood entering the atria via vena cava and pulmonary vein
2. ventricular diastole - blood entering the ventricles from the atria

How well did you know this?

Not at all

Perfectly

What are the events that happen in one heart beat during atrial diastole?

No electrical impulse
Atria fill with blood from vena cava and pulmonary vein
AV valves closed.
Atrial pressure rises above ventricular pressure
Blood starts to pass passively into ventricles

How well did you know this?

Not at all

Perfectly

What are the events that happen in one heart beat during atrial systole?

SA node fires electrical impulse across atria.
Atria contract.
AV valves forced open
Remaining blood is pumped into ventricles
Semilunar valves close

How well did you know this?

Not at all

Perfectly

What are the events that happen in one heart beat during ventricular diastole?

Impulse received by AV node
Delay impulse for a moment to allow atria systole to complete
AV valves close
AV node sends impulse down right and left bundles of His into the Purkinje fibres

How well did you know this?

Not at all

Perfectly

What are the events that happen in one heart beat during ventricular systole?

Ventricles contract from the bottom upwards.
Semilunar valves forced open
Blood is pumped out of ventricles into pulmonary artery and aorta

How well did you know this?

Not at all

Perfectly

Define heart rate. (HR)

The number of times the heart beats per minute.

units = bpm

How well did you know this?

Not at all

Perfectly

What is the average heart rate at rest?

70 bpm

What is the heart rate for endurance athlete?

50 bpm

How can you calculate maximum HR?

200bpm - age

What is it called when the resting HR is less that 60bpm?

bradycardia | caused by increased size and strength of heart known as cardiac hypertrophy

How is cardiac output calculated?

cardiac output = stroke volume x heart rate Q = SV x HR

Define stroke volume. (SV)

The amount of blood ejected from the left ventricle per beat | units = ml

What is the average stroke volume at rest?

70ml

What is the stroke volume for endurance athlete?

100ml

What is Frank-Starling's law of the heart?

SV depends on venous return (VR) VR is the volume of blood returning to the heart If VR increases SV increases and therefore force of contraction

Define cardiac output (Q)

the amount of blood ejected from the left ventricle per minute unit = l/min

What is the average cardiac output at rest?

5 l/min

What is the cardiac output for endurance athlete?

5 l/min

Why does an endurance athlete have bradycardia?

Their heart is so efficient due to hypertrophy that it pumps more blood per minute so their resting heart rate is below 60bpm.

What is sub-maximal?

a low to moderate intensity pf exercise within a performer's aerobic capacity

What is venous return?

the return of blood to the right atria through the veins

What is maximal?

a high intensity of exercise above a performer's aerobic capacity that will induce fatigue

What is the CCC?

Cardiac control centre | a control centre in the medulla oblongata responsible for HR regulation

When is the CCC used?

When a situation arises needing the increase or decrease in hear rate

What is the sympathetic nervous system?

part of the autonomic nervous system responsible for increasing HR specifically during exercise

What is the parasympathetic nervous system?

part of the autonomic nervous system responsible for decreasing HR specifically during recovery

What is the ANS and what does it do?

autonomic nervous system | determines the firing of the SA node

What are the 3 factors which control he activity of the CCC?

Neural control intrinsic control hormonal control

What is neural control?

proprioceptors -->in muscles and joints, tell CCC that movement has increased chemoreceptors -->in aorta and carotid arteries, detect decrease in blood pH due to an increase in lactic acid baroreceptors-->in blood vessel walls, inform CCC of increase in blood pressure

What is intrinsic control?

temperature-->changes affect blood viscosity and speed of nerve impulse transmission venous return-->changes will affect stretch in ventricle walls, force of contraction and therefore SV

What is hormonal control?

adrenaline and noradrenaline--> these are released from the adrenal glands and increase SV and HR

What is vasodilation?

widening of arteries, arterioles and pre-capillary sphincters

What makes up the vascular system?

blood vessels | blood - 45% cells + 55% plasma

Name the types of blood vessels.

arteries + arterioles capillaries veins + venues

What are the features of arteries/arterioles?

Contain blood under high pressure Have a large layer of smooth muscles and elastic tissue to vasodilator and vasoconstrict Arterioles have a ring of smooth muscle surrounding the capillary bed to control blood flow through dilation and constriction

What are the features of capillaries?

Capillary walls are one cell thick | Is where gas exchange takes place

What are the features of veins/venules?

Carry deoxygenated blood Have thin walls Small layer of smooth muscle to allow ventilate and venoconstrict Contain blood under low pressure Have one-way pocket valves to prevent blood flowing backwards against gravity

What is vasodilation?

Widening of arteries, arterioles and pre-capilary sphincters

What is vasoconstriction?

narrowing of arteries, arterioles and pre-capilary sphincters

What is deoxygenated blood?

Blood depleted of oxygen and saturated with carbon dioxide and waste products

What is venodilation?

widening of the veins and venules

What is venoconstricton?

Narrowing of veins and venules