Sickle cell anemia, Infection by housefly, Allergy, AIDS, Radiation effects and ill-effects of tobacco are explained in the following manner:
a) Sickle cell anemia:
It is a genetic disease i.e. a disease transferred from generation to generation. In this disease defective type of hemoglobin (of sickle shape) are contained in red blood cells. This disease is commonly prevalent amongst people living in some parts of Africa. In India, it is found in the tribal areas of Madhya Pradesh, Bihar and in parts of Maharashtra.
b) Infection by housefly:
The housefly is a common carrier of infective organisms. These love to sit on garbage, human waste and food. These transmit micro-organisms from excreta or decaying matter to food through their feet, hair and other parts of the body. This can be easily prevented by covering food as well as garbage with lids.
Some people develop a rash either by eating certain food like fish or start sneezing when exposed to dust or pollen or due to sudden change of temperature. So these people are sensitive or in other words allergic to these things. These substances or conditions are normally harmless. So the unfavorable reaction of the body to these substances is called an allergies reaction. Asthma is caused due to this reaction. Allergies can be prevented by avoiding the offending substance or environment.
The full name of this disease is acquired immune deficiency syndrome. It is caused by a virus which suppresses the immune mechanism of the body and the body becomes susceptible to any disease. Generally this disease is contacted though sexual contact with an infected person. Sometimes during blood transfusion, the infected blood and also infected injection needles may cause this disease. At present, there is no vaccine or medicine that can cure this disease.
The ultra violet rays of the sun affect our cell growth and also interfere with other genetic and metabolic activities. Similarly, gamma rays also damage our cells.
f) Ill-effect of tobacco :
Tobacco consists of a stimulant and poisonous substance. This substance is called nicotine. Prolonged use of tobacco leads to accumulation of tar in nose, throat and lungs. The tar accumulation of tar in nose, throat and lungs. The tar causes cough and irritation. It temporarily increases blood pressure and thus the heart is affected. In this way, heart beating stoppage chances increase. It causes lung cancer. Bidi and cigarette fumes also contain carbon monoxide, hydrogen and cyanide gas also-with un-oxidized nicotine. All these products are injurious to health. Smoking also has a bad effect on non-smokers who inhale the smoke-filled air on non-smokers who inhale the smoke-filled air around them. Thus, smoking is dangerous for health.