blood circulation science NT

heart

muscular pump

blood

a liquid that transports oxygen, digested food and carbon dioxide

blood vessels

a network of tubes that carry blood

veins

carry blood from other parts of body to the heart . has valves to ensure blood flow in one direction

arteries

carries blood away from the heart. has thick muscular wall to withstand high blood pressure

capillaries

supplies blood from arteries to body tissues and organs. has one cell thick wall to allow efficient exchange of gases. has narrow tubes that allows one re blood cell to flow at one time

why we need a healthy circulatory system.

we need a healthy circulatory system for blood to flow smoothly and continuously so that oxygen and food are quickly brought to all the body cells and that carbon dioxide and waste materials are removed from respiring cells

red blood cells

contains a red pigment called haemoglobin that binds to oxygen it also carries oxygen from lungs to all parts of the body

white blood cells

destroys bacteria and other foreign bodies and produces antibodies that help trigger a response to remove the bacteria or virus during an infection

platelets

stops bleeding at wounds by forming a mesh and clotting blood

plasma

transports substances such as carbon dioxide and digested food around the body

what happens when plaque is found near the heart muscles

if plaque is found in an artery that supplies oxygen to the heart muscles blood supply to the heart muscles is cut off. the heart muscles may not receive enough oxygen and stops pumping this results in a heart attack

what happens when plaque is found near the blood that supplies to the brain

if the blockage is in an artery that supplies blood to the brain blood supply to the brain is cut off this results in a stroke , and may result in numbness, paralysis, loss of hearing and eyesight , even death

what causes plaque and what it does

blood flow is slowed down or stopped due to a blockage in the blood vessel it occurs when fats, cholesterol and other substances build up in the walls of arteries forming plaque

blood pressure

when blood moves through the arteries, it pushes against the sides or the walls of the arteries. the amount of force acting on the walls of t he blood vessels is called blood pressure

heart rate or pulse rate

heart rate refers to the number of times the heart beats in one minute. the pulse rate or heart rate of a normal adult at rest can range from 60 to 100 beats per minute. during exercise our pulse rate increases. we also breathe faster and more deeply to take in more oxygen

what happens if our blood pressure is high

it will put extra strain on the arteries , it also increases the risk of getting serious illnesses such as heart disease and stroke

what can high blood pressure be caused by

a diet in saturated fat, cholesterol and salt and a lack of regular exercise

how is plaque formed

excess fat and cholesterol from our diet settles on the inner wall of our arteries and forms plaque

how does plaque affect the internal body

this causes the blood vessel to narrow and blood flow is restricted. blood pushes more forcefully through the narrowed blood vessel, causing blood pressure to increase. over time this may damage the artery wall or even cause it to burst.

how can the lack of exercise and a high intake of salt result in high blood pressure

lack of regular exercise means that the heart is not trained to beat efficiently. over time it may become weak and the body’s cells cannot receive oxygen. high salt intake is also known to increase blood pressure. this may cause health problems like heart attack and stroke