My Science School

          Every man in this world wishes to live long and nobody wants to grow old. But this desire of man is never fulfilled. Growing old is a process that begins with birth itself and continues throughout the life.

          When the child is born, all the parts of his body are tiny. All the biological processes continue with a fast speed. As man grows older, biological changes take place in the body. These changes cannot be prevented. Old age is the culmination of these biological changes. Do you know which are the biological changes brought about by old age?

          With the advancement of age, biological processes slow down, due to which the strength and sensitivity of man also diminish. This is because of the fact that the rate of production of proteins in the body decreases. Changes in the enzymes are also responsible for aging process. With reduced physical activity, man starts losing weight, his eye sight becomes weak and hair go grey. All these are the signs of the old age.

         In old age, changes occur in all the cells and tissues of the body. The cells of kidneys, liver and intestines become weak. Blood vessels become old and consequently they are not able to carry blood and other nutrients adequately to all parts of the body. As a consequence aging increases. As the age advances, eyes, ears, skin, teeth and digestion become weak. Blood circulation becomes irregular. Finally life comes to an end.

          The rate of growing old may be different with different people but old age spares none. This is a definite biological change which cannot be prevented. However, with the help of nutritional food, pure environment and proper exercises, early onset of old age can be prevented.

           There are many theories regarding baldness. Some people treat baldness as the indication of the arrival of old age while some are of the view that bald men are intelligent. Baldness is also treated as a sign of richness. Some people think that bald men are fools. Whatever may be the significance of baldness, one thing is certain that by losing hair, man is deprived of his natural charm.

           Baldness or alopecia is mainly of two types: permanent and temporary. Heredity, age and male sex hormone (androgens) production are three main factors causing permanent baldness. Other causes of permanent baldness are scar producing skin diseases, injuries, inborn lack of hair development and severe injury to hair growing centers caused by chemical or physical agents. Disease of the scalp is one important cause of baldness.

           Temporary baldness may be due to high fever, typhoid, pneumonia, influenza etc. Hairs start falling due to weakness also. Baldness caused by disease and weakness can be cured by nutritive diets and tonics. X-rays, ingestion of meals and drugs, malnutrition, skin disease and endocrine disorders are some other causes of temporary baldness.

          Baldness can be controlled to some extent through proper care of hair and a balanced diet. No successful drug or therapy has yet been developed to treat baldness. Don’t waste money on advertised patent medicines or so called, “cures”!

 

Just as carbohydrates, proteins, fats, inorganic salts and water are the essential parts of our food, vitamins are also necessary to keep the body in good health. Lack or deficiency of vitamins can cause many disorders and diseases like loss in digestive power, weakening of eye-sight, general weakness, tiredness, dryness of skin, inflammation of gums, weakening of bones, beriberi, rickets, etc.

What are vitamins? The word vitamin was coined in 1912 after the Latin word ‘vita’, which means life. In fact, vitamins are organic materials which are found in many food substances and are extremely essential for the proper functioning of the body. They are of many kinds and each vitamin has a separate role in keeping our body healthy. Twenty kinds of different vitamins have already been isolated, out of which six vitamins are most important. These are vitamins A, B, C, D, E, and K.

Vitamin A: Vitamin A is mainly found in milk, butter, cream, cheese, eggs, fish-oil, cabbage etc. It is very essential for the development of the body. Deficiency of vitamin A weakens eye sight and leads to night blindness. Vitamin A protects us from infections, skin diseases and many eye diseases.

Vitamin B Complex: Vitamin B consists of many water soluble vitamins of the same nomenclature. They are known by their chemical names. Their constitution and functions are also different.

Continue reading "Why are vitamins essential for us? "

          The normal body temperature of a healthy man is 98.4°F (37°C). Fever is a condition in which the body temperature rises above the normal. It is a common symptom of disease.

          The heat energy produced by the chemical reactions taking place inside the body is controlled by brain and skin. As long as there is no disease or malfunctioning in the body, the temperature remains 98.4°F. When germs of some specific disease attack the body, pyrogens are produced in the body cells. Consequently, the centres controlling the body temperature are affected and, as a result, body temperature starts rising. This rise in temperature is called fever. The first signs of fever are chills, loss of appetite and a feeling of weakness.

          Fever is a body mechanism that helps us in destroying the germs of diseases. During fever, some of the body organs start working fast and some physiological processes get accelerated. The rate of production of hormones, enzymes and blood cells increase considerably. These hormones, enzymes and blood cells start fighting the germs causing fever. During fever, blood circulation and respiration become faster. Both these processes help the body in getting rid of the poisonous germs present in the body. Fevers are often the symptom of a serious infection.

          There are various kinds of fever – malaria, typhoid, etc. Persistence of any fever for a longer period is not good. During fever, the internal parts become hot and there is deficiency of water causing the contraction of the capillaries of blood and urinary tracts. Protein accumulated in the body gets depleted. Disorder sets in the brain due to high temperature. It is, therefore, a big mistake on the part of anybody, if he or she ignores fever. Though fever is a physiological activity aimed at fighting any disease, it is extremely essential to seek immediate medical assistance once you get it.

A fracture is a break in a bone. Bones may break or fracture in several different ways. A simple fracture is one in which the two ends remain in position, and not much damage is done to the surrounding tissue. In a compound fracture, the broken bone sticks out through the skin. A comminuted fracture is a bone that has splintered or shattered. An impact fracture involves the ends of two bones rubbing each other. A greenstick is a partial break of a bone. In other kinds of fracture large blood vessels may be damaged or the bone ends may be smashed.

A fracture causes pain and inflammation in the area around it. Usually, when a fracture occurs, a doctor must set the bone right so that it may heal properly. A plaster cast is often applied to the limb with the fracture to assure proper healing.

The healing process begins when blood from broken blood vessels clots. After a few days the broken ends of the bone become soft and the space between them is filled with sticky ‘glue’ which contains bone forming cells.

Within two or three weeks, new soft bone tissues completely fill the gap between the broken ends. They slowly harden. The complete healing of a fracture may take several months. The only necessary condition is that the two broken pieces must be held in place for several weeks so that they can grow together properly.

Older people with brittle bones are most apt to get a fracture. Children tend to resist fracture.

             When your skin gets a cut, the broken blood vessels immediately become very narrow. This stops excessive bleeding and helps to keep germs out of the blood. Then substances released into the blood cause it to clot. The blood clot holds the edges of the wound together and hardens into a protective scab.

             Meanwhile white blood cells called neutrophils rush to the wound and begin to engulf the invading germs of dangerous bacteria. Then larger white cells called monocytes appear and engulf more germs, together with any debris. Any germs that escape are dealt with by a third kind of white cells called lymphocytes. These recognize germs as being ‘foreign protein’ or antigens. Then they start the production of antibodies, which are protein substances that stop germs working.

                      In the lower layer (the dermis) of the skin, special cells called fibroblasts move into the wound and start producing new tissues. These new tissues are essential for the healing of the wound. In the upper layer (epidermis), the cells around the wound start multiplying and filling the gap. When the process of new skin tissue development beneath the scab is nearly complete, the scab falls off. In this way the wound gets healed.