PE theory

The cardiovascular system is made up of the heart, blood and blood vessels

What does it do?

• Deliver oxygen to the working muscles
• Deliver nutrients to the working muscles
• Takes away excess carbon dioxide 
• Take away waste products e.g lactic acid

*The heart is made of cardiac muscle which means that it doesn't fatigue and lactic acid does not build up

*The muscle on one side of the heart is bigger than the other beccause one side needs to pump blood to your lungs therefore it is smaller whereas the otherside pumps blood all around the body so it is bigger as it travells a longer distance.

• Arteries are blood vessels that carry blood away from the heart because arteries have to withstand the high pressure of the blood during each heart beat, they have thick, elastic walls which substances cannot pass through

• Veins carry blood towards the heart. Veins have thinner walls which are less elastic, because the blood they transport is under lower pressure. They still do not allow substances to pass through their walls. Veins contain one-way valves which prevent blood flowing backwards.

• Capillaries are very thin blood vessels which have walls that are only one cell thick. This means that substances such as glucose, oxygen, water and carbon dioxide can diffuse through between the blood and the tissues.

1. The left side of the heart pumps oxygenated blood from the lungs, through the aorta to the body tissues (excluding the lungs).

2. Deoxygenated blood returns from the body tissues to the right side of the heart, via the vena cava.

3. It is then pumped to the lungs, via the pulmonary artery where it is oxygenated.

4. Blood returns to the left side of the heart, via the pulmonary vein and is pumped to the body tissues again.

• Systole is the phase of the heartbeat when the heart muscle contracts and pumps blood from the chambers into the arteries

• Diastole is the phase of the heart beat when the heart muscle relaxes and lets the chambers fill with blood. 

Heart rate; The number of times your heart beats per minute 

Stroke volume; The volume of blood pumped out of the heart by each ventricle during one contraction

cardiac output; The amount of blood ejected from the heart in one minute  (HR X stroke volume)

Blood pressure; Pressure of the blood against the walls of the blood vessles ,especially the arteries

• Cardiac hypertrophy is a thickening of the heart muscle  which results in a decrease in size of the chamber of the heart, including the left and right ventricles. A common cause of cardiac hypertrophy is high blood pressure and heart valve stenosis.

increases;

• blood pressure
• heart rate
• stroke volume
• cardiac output
• number of capillaries
• red blood cell count

Blood is made up of red blood cells, white blood cells, platelets and plasma . Adults have about 5.5 litres of blood circulating their bodies.

plasma

This is the liquid part of the blood; it is mainly made up of water. If the plasma did not exist, the solid cells would not be able to flow  around the body, so the plasma gives the other cells a ride

red blood cells

These are very important to a performer. The red blood cell contain haemoglobin ,  substance that allows the transportation of oxygen around the body

white blood cells

These are also very important to a performer .They are responsible for seeking out and destroying infections.The white blood cells can slide through the walls of the blood vessel and attack bacteria at the site of the infection. The white blood cells keep the performer healthy.

platelets

These play a vital role in maintaining the health of a sports performer .Platelets aid clotting: If the performer recieves a cut or a graze, platelets are dispatched to put a plug in thee hole in the skin so that there is no further blood loss.

key words

• intercosal muscles-muscles between the ribs that contract to enlarge the ribcage
• diaphram-muscles that pull down when breathing in
• tranchea-tube for the passage of air
• ribs-bones that form a cage to protect the organs in the chest area
• Bronchi-one of the two branches of the tranchea
• alveloi- smaller sacks at the end of the bronchioles
• broncioles-smaller air tubes from the bronchi into the lungs

inspiration vs expiration

Inspiration

1. the intercostal muscles contract, expanding the ribcage

2. the diaphragm contracts, pulling downwards to increase the volume of the chest

3. the pressure inside the chest decreases and air is pushed into the lungs

expiration

1. the intercostal muscles relax, the ribcage drops inwards and downwards

2. the diaphragm relaxes, moving upwards to decrease the volume of the chest

3. pressure inside the chest increases and air is pushed out of the lungs

Breathing rate- is the number of times you breathe in and out in 1 minute

tidal volume- is the volume of air you breathe in and out in one cycle of normal breathing 

vital capacity - is the maximum volume of air you can forcibly breathe in and out.

overview   -Gas exchange is the delivery of oxygen from the lungs to the bloodstream, and the elimination of carbon dioxide from the bloodstream to the lungs. It occurs in the lungs between the alveoli and a network of tiny blood vessels called capillaries, which are located in the walls of the alveoli.

The walls of the alveoli actually share a membrane with the capillaries in which oxygen and carbon dioxide move freely between the respiratory system and the bloodstream. Oxygen molecules attach to red blood cells, which travel back to the heart. At the same time, the carbon dioxide molecules in the alveoli are blown out of the body with the next exhalation.