Cardiovascular system

Explain what the process of atherosclerosis is

build up of fatty deposits in the coronary ateries

Explain what atheroma is

fatty deposits

Explain what agina is

pain in the heart

Explain what blood pressure is

force exerted by the blood against the blood vessel wall

Explain the effect of low density lipoproteins

increased risk of heart disease

transport cholesterol in the blood tissues

Explain the effect of high density lipoproteins

lower the risk of heart disease

transport excess cholesterol in the blood back to the liver where it is broken down

Explain what an ischaemic stroke is

blood clot stops the blood supply

Explain what a haemorrhagic stroke is

weakened blood vessel supplying to the brain bursts

Explain how the stroke volume can be increased

venous return

elasticity of cardiac fibres

contractility of cardiac tissue

How can the maximum heart rate be calculated

220 - age

Define bradycardia

resting heart rate below 60 bpm

Define cardiac hypertrophy

heart becomes bigger and stronger due to a thickening of the muscular wall

How can the cardiac output be calculated

stroke volume x heart rate

Explain the cardiac conduction system

SAN (sino-atrial node) sends a wave of excitation across the atrial walls

AVN (atrio-ventricular node) delays the impulse to enable the atria to empty and ventricles to fill

Bundle of His sends impulse down the ventricular walls

Purkjne fibres recieve impulse and the ventricles contract

Describe what myogenic is

heart muscle generates its own heart beat

Define the sympathetic system

increases heart rate

‘flight or figh response’

Define the parasympathetic system

decreases the heart rate

‘rest and relax’

Explain the process of anticipatory rise before exercise

hormone adrenaline is released by the nervous system

stimulates heart rate to increase both the speed and force of contraction

increases cardiac output

more oxygenated blood pumped to the working muscles

Define the medualla oblongata

regulates the processes that keeps us alive

What do chemoreceptors detect

changes in blood acidity (carbon dioixide levels)

What do proprioreceptors detect

muscle movement

What do baroreceptors detect

changes in the blood pressure

Where are the chemoreceptors found

carotid atery

aortic arch

Describe what vascular shunting is

redistribution of cardiac output to where oxygen is needed most