Blood• Plasma• Platelets• White Blood Cells• Red Blood Cells
Plasma• Transports dissolved substances: Hormones Fibrinogen, a protein which helps blood to cot. Food (glucose and aminoacids) Waste substances, urea
Red Blood Cells• This blood cells are red because of a red pigment called Haemoglobin.• As this cells pass through the lungs, oxygen diffuses into the cell.• The oxygen and haemoglobin form a new chemical called oxyhaemoglobin, which is carried around the body to organs and tissues.• When the red blood cells reach cells in the body that have little oxygen, the oxyhaemoglobin splits back into O2 and Haemoglobin.
Red Blood Cells Shape• Red blood cells have a biconcave shape with a large surface area.• The large surface area allows more oxygen to diffuse in and out of cells.• Red Blood cells do not have a nucleus, and that allows more room for haemoglobin.
Role of White Blood Cells Phagocyte• White Blood Cells Body´s defense system Lymphocyte• Phagocytes can leave the blood channel and enter any tissue.• These blood cells swarm any bacteria they find, enclose it inside them and Digest it. This process is called Phagocytosis.
Role of White Blood Cells• Lymphocytes are made in glands called Lymph Nodes.• When pathogens enter the body, white blood cells recognize the foreign proteins, called antigens, on the outside of the pathogens.• White blood cells produce proteins called antibodies, which destroy the pathogens.• This antibodies can also destroy the toxins produced by germs. There is a different kind of antibody for every germ.• This actions are known as immune responses. The protection the immune responses give you is known as natural immunity.• Sometimes the lymph nodes swell up during an immune response, and it is possible to feel the nodes in your neck,
Platelets• Platelets are small fragments of red blood cells, which ensure that your blood clots when you cut yourself.• A clot protects against microbes entering your body through the wound.• A clot is formed when the platelets clump together.• This triggers off a chemical reaction, turning the soluble protein fibrinogen into fibrin, which doesnt dissolve in blood• These fibrin fibres create a web, which traps the blood underneath and leaves a clot or scab on the surface.