Exercise and Movement

What is systolic blood pressure?

Pressure of blood against artery walls during vesicle contraction

What is diastolic blood pressure?

Pressure of blood against artery walls when ventricles relax

What are the 4 sets of specialised tissue in the heart?

Sinoatrial Node

Atrioventricular Node

Bundle of His

Pirkunji Fibres

Which body system controls heart rate?

The Central Nervous System,

Which nervous system will speed up the heart rate

Symapthetic nervous system = speed up

aka accelerator nerve

Which nervous system will slow down the heart rate?

The parasympathetic nervous system = slow

aka vagus nerve

How does the nervous system trigger a change in the heart rate?

By targeting/stimulating the sinoatrial node

What hormone targets the SAN?

Adrenaline, can cause vasocnostriction

What is vasoconstriction?

When the muscles in blood vessels contract, narrowing the lumen, increasing blood pressure, restricting blood flow to specific areas.

The point:

How does the symapthetic/accelarator nerve speed up the heart rate?

By releasing noradrenaline at the SAN

Explain how an electrical impulse will travel through the heart to make it beat:

1 - the sinoatrial node starts the sequenceby generating an electrical impulse. The impulse depolarizes the left and right atrium, stimulating it to contract

2 - the impulse travels to the atrioventricular node, it pauses to allow ventricular filling

3 - impulse travels down bundel of his, causing septal depolarisation

4 - the impulse is carried through the purkinji fibres, depolarising the left and right ventricles , causing asimultaneous contraction

How does the parasympathetic/vagus nerve slow down the heart rate?

By releasing acetylcholine at the SAN

During inspiration vs expiration, what happens to the diaphragm?

Inspiration, diphragm flat/contract

Expiration, diaphragm up/relax

When reading an electrocardiogram what does the following tell you?

• P wave

• QRS wave

• T wave

• P - measures atrial depolarisation

• QRS - measures ventricular contraction

• T - measures ventricular repolarisation (relax)

What would an enlarged P wave tell you?

You have an enlarged atrium

What would an enlarged Q wave tell you?

You have a heart attack

What would an enlarged T wave tell you

Too much potassium in blood stream

What would a flat T wave tell you

oxygen is being restricted towards heart, cardiovascular disease

What does an ecg measure?

The electrical impulse in the heart, which is then turned into a diagram and can tell you about how the heart is contracting and if there are any specific issues

What controls breathing rate and depth of ventilation?

The brain

Which nerve stimulates the diaphragm?

Phrenic nerve

Which nerve stimulates the external intercostal muscles?

Intercostyal nerve

What is the respiratory centre?

The medulla oblangata

The Pons

What is the definition of cardiac output? and what is the average cardiac output?

The total amount of blood pumped out by both ventricles in a minute

average - 5.25l at rest

7-8x more exercising

What two things determine/influence the cardiac output?

Heart beat and stroke volume

wHAT IS STROKE VOLUME?

Volumne of blood pumped out of one ventricle in one heartbeat

What different factors could affect stroke volume?

heart beat

the sympathetic nervous system - can increase contraction force

exercise (regular exercise can make permanent changes)

venuous return

Hypertension (high blood pressure)

Atheroscelerosis (fat buiild up in artery walls

What is the frank starling law?

The more blood filled into the ventricle, the greater force it will contract

so the more the muscle stretches the harder it will eject the blood out, inceasing stroke volume

What is the autonomic nervous system?

a component of the peripheral nervous system that regulates involuntary bodily functions

If the diameter of a blood vessel increases his is called___ and this ___ the blood pressure

1 - vasodilation

2 - decreases blood pressure

If the diameter of a blood vessel decreases this is called___ and this ___ the blood pressure

1 - vasoconsriction

2 - increases blood pressure

What is blood pressure

pressure of blood against the blood vessel walls

What are the three layers within a blood vessel?

Tunica intima

tunica media - smooth muscle (contraction, expansion layer)

tunica externa - contains sympathetic neurons, controllinng tunica media

What is a precapillary sphincter and shunt?

two flaps that baso can close so that blood doesnt enter the capillaries or oxygenate the tissue at the sitte.

It does this ecause it could not be necessary at a specific time another organ could need it more

so the blood is diverted through a metarteriole, centrechanel-thorough fare channel (shunt is that diversion)

What is a baroreceptor?

monitor blood pressure changes

What is a chemoreceptor?

detect chanes in chemical balances, eg co2