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Our blood has two basic parts: blood cells, which are also called blood corpuscles, and plasma, the fluid in which the blood cells are suspended.

Most of the blood cells are red blood cells. Their dimensions are very small: if these cells, invisible to the naked eye, were collected from the entire body and placed one-thick on a flat surface they would occupy an area of 1000 sq.m. The red colour of these cells which are called erythrocytes is due to the hemoglobin they contain, which combines with oxygen in the lungs and releases it to the tissues as the blood circulates through the body. The red cells also carry the waste product carbon dioxide from the tissues to the lungs so that it can be exhaled. The life span of one red blood cell is about three and a half or four months. New erythrocytes are formed in the red bone marrow, from whence they emerge into the blood to take up their work.

Our body also contains white blood cells, which protect the body from infection. There are several different kinds of white blood cells. Most of them are neutrophiles, which attack and engulf bacteria. Another kind, the lymphocyte, recognizes foreign cells, infectious agents, and participates in the body’s immune reaction against them.

A third type of blood cell is the platelet. Platelets gather wherever a blood vessel is injured, to plug the hole. This is the first stage in the blood clotting process.

Most blood cells are produced in the bone narrow. However, lymphocytes are made in the spleen or in the lymph glands, which are found in the neck, armpits, groin and many other parts of the body. The spleen and lymph glands, together with the channels and ducts connecting them, are called the lymphatic system. When red blood cells and platelets become old or defective they are filtered out of the bloodstream and broken down by the spleen, and also by the liver and lymph glands.

Disorders of the blood are grouped as follows: lack of hemoglobin, which causes anemia; disorders in clotting, which cause bleeding and bruising; cancerous changes in the white cells, which cause leukemia; disorders in the production of blood cells in the bone marrow; and disorders that affect the lymphatic system.

Anemia is defined as a decrease in either hemoglobin or the number of red blood cells to below the normal level. Iron is essential ingredient in hemoglobin. If there is not enough iron in the body, there cannot be made enough hemoglobin. This form of anemia is called iron-deficiency anemia. A severe shortage of vitamin B12 in the body also affects the production of red blood cells. This is called B12 deficiency anemia. Lack of folic acid in the body has the same effect, and this is called folic acid deficiency. In hemolytic anemia the red blood cells are destroyed more quickly than they normally would be and the number of red blood cells in the body may fall well below normal. Inherited defects of the blood such as sickle-cell anemia cause the body to produce abnormal hemoglobin.

All these types of anemia may be found in children but the most common one is iron-deficiency anemia. Insufficient iron in the body causes an adequate production of hemoglobin, and therefore leads to iron-deficiency anemia.

Normally, extra iron is stored in the body and then used to produce hemoglobin in newly developed red blood cells. Most of this iron is recovered as old red blood cells are destroyed. The small amount of iron lost from the body is replaced by iron absorbed from the diet. If the person loses more iron than he is able to absorb he may become anemic. There are three general causes for a lack of iron reserves: there may not be enough iron in the diet; the digestive system is unable to absorb iron, even though there may be enough of it in the diet; the iron reserves may become depleted through excessive loss of blood.

The most frequently observed type of anemia among very young children is anemia caused by faulty nutrition. Such anemia is rarely seen in breast-fed infants. If an infant receives a monotonous milk or cereal dietary and has not enough vitamins he will develop anemia; therefore bottle-fed babies chiefly suffer from anemia.

Anemia associated with some disease is not uncommon in young children Such anemias are either a result of the direct action of the bacterial toxin on the bone marrow, or are caused by the monotonous and restricted diet employed for the treatment of the basic disease.

The most typical form of anemias among children of preschool ages are those caused by a worm diseases or by faulty hygiene.

The disease in older children would not have developed provided they had not neglected fresh air and sun, physical training and sports.

The characteristic symptoms of anemia include paleness, fatigue, weakness, fainting, breathlessness and palpitations. And no doctor will ever risk diagnosing anemia unless he first does blood test.

Anemia is treated by means of numerous excellent preparations the pharmaceutic industry provides us with. However one form of treatment is irreplaceable in all types of more or less far-gone anemia: this is blood transfusion.

Anemia, as any other disease, is easier to prevent than to cure. A most important condition for preventing anemia is proper management of nutrition from the very first days of the baby’s life. The best food for infants is breast milk. As the child grows older his food must become varied. No less important are proper hygiene, hardening procedures and fresh air.


Words to remember:


Pallor, skin, invisible, entire, surface, life span, to carry, to develop, faulty, to neglect, to harden, to explain, numerous, to prevent, to cure, therefore.



Date: 2015-04-20; view: 1869

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