Physical Education: Circulartory system

Cardiovasclur system have three pain componments

 .Blood vessels

.The heart

.Blood

Circulatory system consists of two circuit the blood travel through Pulomary and systemic. Exercise effects these two system  to the heart t pump blood around the body faster and that making you exercise longer.

The Pulomary circuit carries the blood to the lungs to be oxgenated and then back to the heart. In the lungs carbon dioxide is removed from the blood. Blood is then taken up by the haemoglobin to the red blood cells.

The Systemic circuit carries blood around the body to deliever the oxgen and return de-oxgenated blood to the heart. blood also carries nutrient and waste.

Artieries carry oxgeneted blood from the heart to the rest of the body(organ's)

Veins carry de-oxgenated blood from the heart

Stroke volume- the volume of blood pumped from the heart in eachbeat.  

Cardic output- amount of blood pumped out of the heart in one minute . 

Heart Rate- amount of beats per minute. (he amount of blood is calcuted by Heartrate x Stroke volume = Cardic output )                                                                                                                

The heart has four chambers. The two atria collect the blood. The two ventricles pump the blood out of the heart.

Valves prevent the blood from flowing backwards.

The septum separates the two sides of the heart.

The right side of the heart pumps de-oxygenated blood (blood not containing oxygen) to the lungs to pick up oxygen. The left side of the heart pumps the oxygenated blood from the lungs around the rest of the body.

ther are three types of blood vessels;Arteries- Carry blood away from the heart (always oxygenated apart from the pulmonary artery which goes to the lungs)

• Have thick muscular walls
• Have small passageways for blood (internal lumen)
• Contain blood under high pressure

Veins- Carry blood to the heart (always de-oxygenated apart from the pulmonary vein which goes from the lungs to the heart)

• Have thin walls
• Have larger internal lumen
• Contain blood under low pressure
• Have valves to prevent blood flowing backwards
• 

Capillaries- Found in the muscles and lungs

• Microscopic – one cell thick
• Very low blood pressure
• Where gas exchange takes place. Oxygen passes through the capillary wall and into the tissues, carbon dioxide passes from the tissues into the blood

Blood has four componments:

Plasma

• Fluid part of blood
• Carries carbon dioxide, hormones and waste

Red blood cells

• Contain haemoglobin which carries oxygen
• Made in the bone marrow. The more you train the more red blood cells are made.

White blood cells- An important part of the immune system, they produce antibodies and destroy harmful microorganisms

• Made in the bone marrow
• 

Platelets

• Clump together to form clots
• Protect the body by stopping bleeding

When exercising blood does the following things:

• Transports nutrients and waste
• Delivers oxygen to the working muscles
• Removes heat (temperature regulation)
• Dilutes/carries away lactic acid (acidic balance)

Blood pressure increases when you exercise, but is lower at rest when you are fit. It is also affected by age, smoking, stress, diet and weight.

Blood pressure- the force of blood againt your artery wall.