photo.jpg

## How is it? You may be curious to know how the antibiotics kill the germs. Here are two examples: - Penicillin interferes with cell wall formation and hence the bacteria are unable to grow and multiply. - Streptomycin binds to bacterial ribosomes which are then unable to synthesise proteins and...

## How is it? You may be curious to know how the antibiotics kill the germs. Here are two examples: - Penicillin interferes with cell wall formation and hence the bacteria are unable to grow and multiply. - Streptomycin binds to bacterial ribosomes which are then unable to synthesise proteins and the bacteria are unable to grow and multiply. ## 17.7 Sulphonamide group of medicines Since ancient times, man has been trying to discover newer and newer medicines to cure diseases. He tried a variety of plant and animal products, many of which worked well. He also tried various chemical substances, and some of these yielded good results. This is how chemotherapy (treatment by the use of chemicals) was developed. In 1910, a drug called salvarsan (based on an arsenic compound) was produced. It killed the germs of syphilis as well as of sleeping sickness. But frequently, it proved poisonous to the patient as well. In the 1930s, a group of chemicals known as sulphonamides were discovered which proved effective in many types of bacterial diseases. Sulphadiazine and sulphanilamide are two such sulpha drugs. These are synthetic drugs and they interfere with the metabolism of bacteria which are thus killed. Sulphonamides are now rarely used, and that too, in combination with antibiotics, for certain ailments. ## Progress Check 1. Correct the following statements if they are false (without changing the first word): - DDT is an antiseptic. - Penicillin is a disinfectant. - Disinfectants are applied on the body. - Deodorants are both antiseptic as well as disinfectants. - Alexander Fleming discovered the first sulphonamide. - Antibiotics cannot be made synthetically. - Sulphonamides are now rarely used. 2. List any three uses of antibiotics. ## Review Questions **A. Multiple Choice Type** (Select the most appropriate option in each case) 1. Penicillin is - (a) an antiseptic - (b) a disinfectant - (c) an antibiotic - (d) an anti-toxin (c) Strong chemicals obtained from fungi. (d) Chemicals that are applied on the skin to kill bacteria. 6. The letter "B" in the name BCG vaccination stands for: ## C. Short Answer 1. Mention if the following statements are true or false (F). - (a) Lysol is an antibiotic. - (b) Sweat and tears can kill germs. - (c) Our body can produce antibodies against different antibodies. - (d) Salk vaccine is used for typhoid. - (e) Treatment by the use of herbs is called allopathy. - (f) Alexander Fleming discovered the first antibiotics. - (g) DDT is a disinfectant. - (h) Vaccine provides immunity against diseases. - (I) Penicillin was discovered in 1928. - (j) BCG is the vaccine which provides immunity against tuberculosis. 2. Differentiate between: - (a) Antiseptic and disinfectant. - (b) Antiseptic and antibiotic. - (c) Disinfectant and antibiotic. - (d) Vaccination and immunization. - (e) Active immunity and passive immunity. - (f) Innate immunity and acquired immunity. 3. Name any three vaccines and write the diseases they provide immunity against. 4. Given below is a list of some common diseases against which vaccines are available. Fill up the name of the vaccine used for each.