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Blood - Its structure and components

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* Blood is the fluid of life, transporting oxygen from the lungs to body tissue and carbon dioxide from body tissue to the lungs. * Blood is the fluid of growth, transporting nourishment from digestion and hormones from glands throughout the body. * Blood is the fluid of health, transporting disease fighting substances to the tissue and waste to the kidneys. * Blood is a very important fluid! * The average adult has about 10 pints of blood. Blood is made from both solid and liquid components. The liquid part is called plasma and in the plasma floats the solid components; these are the white and red blood cells and the platelets. Plasma is the straw-coloured, clear liquid that holds blood cells and platelets in suspension. Though plasma is approximately 90% water it is still an essential ingredient for human survival. It might seem like plasma is less important than the blood cells it carries. ...read more.


As blood passes through the lungs, oxygen molecules attach to the hemoglobin. As the blood passes through the body's tissue, the hemoglobin releases the oxygen to the cells. The empty hemoglobin molecules then bond with the tissue's carbon dioxide or other waste gases, transporting it away. White blood cells, or leukocytes, play a key part in your body's defense against infection. They protect your body from disease by either phagocytizing (eating) bacteria or producing antibodies that destroy infectious particles. Though most of white blood cell activity takes place outside of the circulatory system, these cells use the blood to reach sites of infection and disease. A drop of blood can contain anywhere from 7000 to 25,000 white blood cells at a time. If an invading infection fights back and persists, that number will significantly increase. However a consistently high number of white blood cells is a symptom of Leukemia, a cancer of the blood. ...read more.


Both scabs and bruises are clots that lead to healing. Some clots however can be extremely dangerous. A blood clot that forms inside of a blood vessel can be deadly because it blocks the flow of blood, cutting off the supply of oxygen. A stroke is the result of a clot in an artery of the brain. Without a steady supply of oxygen, the brain cannot function normally. If the oxygen flow is broken, paralysis, brain damage, loss of sensory perceptions, or even death may occur. Without platelets we would bleed to death when we got a paper cut! Red blood cells: as the name would suggest these are red coloured cells. Their red colour comes from the hemoglobin within them. They are doughnut shaped because this gives them a larger surface area, which enables them to carry more oxygen and to bend when necessary. Their hemoglobin makes blood red. White blood cells: these cells come in different shapes and colours depending on how they go about their "job". Some white blood cells produce antibodies and so are marginally smaller than those that eat the offending germs. ...read more.

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