(iv) infection Common ailments like cold, influenza (flu), cough, polio, chicken pox are caused by viruses. (c), Question 6. What are antibiotics? How can we prevent a person from getting Hepatitis B ? Question 22. Answer: (iv) butterfly Take two pots and fill each pot half with soil. Jams and jellies are preserved by Question 3. Answer: Question 10. THANKS FOR READING., 87 [NCERT] Keep it covered in a warm place for 4-5 hours. Pay Now | Citrus canker, a bacterial disease, affects trees of citrus fruit and is spread by air. Question 15. a medicine obtained from some microorganisms,that inhibits the growth or destroys the harmful microorganisms that cause diseases in ​animals including human beings.for ex penicillin is an antibiotic that is obtained from a microorganism,penicillum. Answer: Question 17. (b), Question 4. [KVS 2007] Write 10 lines on the usefulness of microorganisms in our lives. [NCERT] Since viruses reproduce in the host cell, scientist regard viruses as a link between living and non-living. The sugar is converted into alcohol by yeast and this process is known as Fermentation. Vaccines are usually dead or inactivated organism or compounds purified from them.Here is a video showing how our immune system works with respect to the vaccines and antibodies: Activity 1 (NCERT Textbook, Page 17) Give two examples where microorganisms are useful at home. Viruses reproduce only inside the host organisms that is, bacterial, plant or animal cell. Question 29. They can only be seen with the help of microscope. Define fermentation. Causative microorganisms – Bacteria. The harmful microorganisms present in excreta and garbage easily stick to its fine array of body hair and are thus, transferred to food stuffs whenever they sit on them and a result food gets poisoned. What will happen if yeast powder is put in sugar solution and kept for few hours ? Question 20. Question 21. It is better to avoid contact with the infected person. (c) Carrier of malaria-causing protozoan is, (d) The most common carrier of communicable diseases is, (e) The bread or idli dough rises because of, (f) The process of conversion of sugar into alcohol is called. number, Please choose the valid Antibiotics should be taken after consulting a doctor. Question 1. (iv) yeast Points. (ii) grinding The low temperature in the refrigerator inhibits the growth of microbes. Question 4. NCERT Solutions Class 8 Science Chapter 2 Microorganisms: Friend And Foe Here on AglaSem Schools, you can access to NCERT Book Solutions in free pdf for Science for Class 8 so that you can refer them as and when required. Some specific microorganisms are helpful in manufacturing of antibiotics. Answer: Question 4. Name the groups in which microorganisms are broadly classified. Antibiotics are a type of antimicrobial designed to target bacterial infections within (or on) the body. Microorganisms are used for the large scale production of alcohol, wine and acetic acid (vinegar). Typhoid is transmitted through water. Tuberculosis is a highly infectious disease. NCERT Solutions for Class 8 Science Chapter 2 Microorganisms: Friend and Foe is given below. “the fermentation of organic matter by micro-organisms in the gut” Answer: Cholera and tuberculosis can be prevented by vaccination. Answer: bacterium absorbs the atmospheric nitrogen and converts it to nitrates. Name the causative microorganism of tuberculosis and its mode of transmission. [DAV2005] Activity 3 (NCERT Textbook, Page 20) [KVS 2008, DAV 2006] (b) pasteurisation What are weeds? What do you see? [DAV2006] Vaccination is a method to immunise the body against diseases by making the body’s immune system produce antibodies against the disease-causing microbe in the vaccine. NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe Topics and Sub Topics in Class 8 Science Chapter 2 Microorganisms Friend and Foe: Section Name Topic Name 2 Microorganisms Friend and Foe 2.1 Microorganisms 2.2 Where do Microorganisms Live? Can you store pickles in iron containers ? Question 4. (d) Some algae. Ask questions, get answers, help others and connect with people who have similar interests. 1) We should not take overdose of antibiotics. Answer: Answer: Question 25. (d) bacteria, Question 2. 19 [KVS 2005] beaker filled upto 3/4 with water. We can also use mosquito repellant creams and mosquito nets. Salmonella typhi. Answer: (iv) spider Answer: Microorganisms that grow on our food sometimes produce toxic substances. Most students have answered these kinds of questions before and for this reason, most students tend to do quite well with them. They are used to cure a variety of diseases. How are cholera and typhoid transmitted ? Answer: Question 4. (b) jams Question 22. What precautions must be taken while taking antibiotics? In pasteurisation, the milk is heated to 62.5°C for 30 minutes or to 71.5°C for 15 seconds. bacteria. Use Coupon: CART20 and get 20% off on all online Study Material, Complete Your Registration (Step 2 of 2 ), Free webinar on Robotics (Block Chain) Learn to create a Robotic Device Using Arduino. Question 28. Match the organisms in column A with their action in column B. Diseases-causing microorganisms are called pathogens. Streptomycin, tetracycline, penicillin, etc. They convert dead organic matter into simple soluble minerals and gases, which can be used again by plants. We should not allow water to collect in coolers, flower pots, etc. (b), Question 2. Download free PDF of best NCERT Solutions , Class 8, Science, CBSE- Microorganisms - Friend and Foe . Question 35. We can not store pickles in iron containers because the acid present in the pickles reacts with iron. Why is it important to vaccinate small children ? (b) Fungi No, microorganisms cannot be seen with the naked eye. The complete dose of the antibiotics should be taken as prescribed. (ii) alcohol, (b) The following is an antibiotic: Ringworm is caused by fungi. Chemicals (salts, etc.) Question 7. Uses of fungi: Question 7. Topics and Sub Topics in Class 8 Science Chapter 2 Microorganisms Friend and Foe: Question 1. (a) malaria If you take antibiotics when not needed, you help bacteria in your body to develop resistance to them. [KVS 2006, MSE (Chandigarh) 2008] Answer: One must finish the course prescribed by the doctor to make the drug more effective. Points, 20 (b) nitrogen A person bitten by dog gets What are microorganisms ? Question 10. They are just one class of antimicrobials, a larger group of Tuberculosis is a highly infectious disease. How is common cold spread ? Several microbes causes diseases in plants and thus reduces the yield. Microorganisms cause diseases in human beings, plants and animals. Answer: Antibiotics Guide Medically reviewed by Leigh Ann Anderson, PharmD.Last updated on June 11, 2019. Name the toxin released by T.B. whenever we fall ill the doctor may give us some antibiotic tablets, capsules or injections such as penicillin.The source of these medicines is nothing but the microorganisms. Answer: Answer: Question 31. Meat and fish are preserved by covering them with dry salt to check the growth of bacteria. A housefly gets attracted towards garbage and excreta. NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe Topics and Sub Topics in Class 8 Science Chapter 2 Microorganisms Friend and Foe: Section Name Topic Name 2 Microorganisms Friend and Foe 2.1 Microorganisms 2.2 Where do Microorganisms Live? It is then rapidly cooled to 10°C and packed in airtight containers. Antibioticsare medicines produced by certain micro-organisms to kill other disease-causing micro-organisms. Email, Please Enter the valid mobile Microorganisms are harmful to us in many ways. Question 11. School Tie-up | Video Format solution based on NCERT Solutions 2020-21 is also available. Dead or weakened microbes are used in the preparation of vaccines. Answer: Put the pots aside. Each class typically contains several antibiotics that have been discovered over time or are modified versions of previous types. The following precautions must be taken before using antibiotics-. Take 500 ml. Solution: Question 16. Question 13. , Answer: Microorganisms exhibiting the characteristics of living and non-living organisms are known as Add half a spoon of yeast powder to the sugar solution. [MSE (Chandigarh) 2005, 2007] Algae and fungi are multicellular. Question 16. 3.   we should take antibiotics only after consulting a qualified doctor. A sore throat, throbbing head, and aching body are all signs of impending doom. Name two carriers of disease-causing microbes. (d) algae What do you observe after two hours? How does food become ‘poison’ ? NCERT Book for Class 8 Social Science (History) Chapter 4 Tribal, Dikus and The Vision is available for reading or download on this page. Give one example each of acute and chronic diseases, Mention any two causes of baby’s disease. (vi) (f). [NCERT] Question 15. Answer: Differentiate between acute and chronic diseases. Answer: (c) only (iii) Q5. Answer: The process of conversion of sugar into alcohol is called fermentation. They are manufactured by growing specific microorganisms. (a) Bacteria These notes are helpful to revise the huge syllabus in a short time and make an … Question 37. Answer: What are preservatives ? Question 1. NCERT solutions class 8 science chapter 2 microorganism friend and foe are provided here to help the students clear their doubts. Antibiotics are compounds that are effective in treating infections caused by organisms such as bacteria, fungi and protozoa. Give reasons in support of your answer. Pickles are preserved by adding salt or acid. (c) idlis Influenza and cough. Question 24. [MSE (Chandigarh) 2008] Question 40. Name one plant disease caused by bacteria and its mode of transmission. How is pasteurised milk obtained ? Answer: Question 11. Answer: are common antibiotics. Name the diseases for which oral drops are given as vaccination. All NCERT textbook questions have been solved by our … (ii) moulding Cholera is transmitted through water or food. (a) fungi (c) Alcohol is produced with the help of _____ [DAV2007] The lesson covers the complete explanation of class 8 Chapter 2 Microorganisms.Topics covered are Introduction to Micro-organisms and microbiology, different types of Micro-organisms, Useful and Harmful Micro-organisms.. How to avoid spreading of Micro-organisms has been discus (d), Question 3. Learn more about how antibiotics work and take a short quiz at the end. Question 7. Answer: Tick the correct answer. These medicines kill or stop the growth of the disease-causing microorganisms. How are meat and fish preserved ? Science_and_technology_(solutions) Solutions for Class 9 Science Chapter 8 Useful And Harmful Microbes are provided here with simple step-by-step explanations. What precautions must be taken while taking antibiotics? The applications of various helpful microorganisms are explained in the class 8 Vaccine is given to healthy persons to prevent occurrence of disease. These make the food poisonous causing serious illness and even death. (ii) cockroach Answer: Microorganisms spoil food and cause food poisoning. Microbial diseases which can spread from an infected person to a healthy person through air, water, food or physical contact are known as communicable diseases. Answer: Blue-green, algae, also called cyanobacteria, can fix atmospheric nitrogen into usable , compounds. Name any two items that are prepared by using yeast. Terms & Conditions | Antibiotics are the chemicals which inhibit the growth of  pathogenic microorganisms in our body thus helps us to control and cure dieseases like, typhoid, diptheria, pnumonia and tuberculosis. It is observed that plant waste in pot A has been decomposed, whereas the polythene bags, empty glass bottles and broken plastic toys in pot B did not undergo such changes. Privacy Policy | Write a short paragraph on the harms caused by microorganisms. [MSE (Chandigarh) 2008]. Such medicines are called antibiotics. (c) typhoid Answer: Answer: Points, 105 Franchisee | Answer: Microorganisms are broadly classified in four groups: bacteria fungi protozoa algae Question 2. (a) Are bacteria plants or animals ? (a) bacteria Microorganisms are useful in our lives in the following ways : Question 3. Can microorganisms be seen with the naked eye? 2.3 Microorganisms and Us 2.4 Harmful Microorganisms 2.5 Food Preservation 2.6 Nitrogen Fixation 2.7 […] (c) bacteria Answer: Microorganisms are useful to us in many ways. An antibiotic can also be classified according to the range of pa… Answer: (iii) growth of yeast cells, (f) The process of conversion of sugar into alcohol is called Did you find the dough rising? Any substance that inhibits the growth and replication of a bacterium or kills it outright can be called an antibiotic. Anthrax in cattle is caused by (d) Cholera is caused by ______ (i) sodium bicarbonate Get here the chapter notes on CBSE Class 9 Science: Why Do We Fall Ill. It is important to remember that antibiotics should be taken only on the advice of a qualified doctor. (b) tetanus Dissolve 2-3 teaspoons of sugars in it. (e) —> (iii) Draw a labelled diagram of Penicillium. askiitians. Answer: Some children fall ill more frequently than other living in the same area due to their weak immunity, or slow immune response. Use of oil and vinegar prevents spoilage of vegetables and fruits because bacteria cannot live in such an environment. [MSE (iChandigarh) 2007]. (i) ant If not, how can they be seen ? [KVS 2006] Some microorganisms are taken as probiotics, that are believed to provide health benefits when consumed. Microorganisms are classified on the basis of their size into four major groups. Add a small amount of yeast powder and knead to make a soft dough. Answer: Answer: It is inspired by … You can improve your knowledge within a short period by referring to Karnataka Board Class 6 English Chapter 8 Bacteria are useful to us as : Question 8. (iv) oxygen Antibiotics as their name suggests are the medicines used to kill or stop the growth of the disease-causing microorganisms. Answer: Answer: Careers | Answer: Name the type of microorganism … Answer: Some of these, such as fungus growing on bread, can be seen with a magnifying glass. (a) Yeast is used in the production of Bacteria are used in the production of vinegar, curd, cheese, etc. How does a housefly transmit diseases ? Sodium benzoate and sodium metabisulphite are added to jams and squashes to preserve them. Antibiotics are ineffective against the viral infections. Answer: subject, Structural Organisation in Plants and Animals. Answer : Microorganisms are harmful in many ways. Name two multicellular microorganisms. (iv) kneading Put plant waste in pot A and things like polythene bags, empty glass bottles and broken plastic toys in pot B. Microorganisms are present in soil, water, outer space and inside the body of animals. Sitemap | Question 8. Some bacteria and blue-green algae are able to fix nitrogen from the atmosphere to enrich soil with nitrogen and increase fertility, are known as biological nitrogen fixers. (a) Microorganisms can be seen with the help of a _____ The viruses may enter the body of a healthy person while breathing. Answer: Bacteria are used in sewage disposal plants. Microorganisms are organisms that are so small that they can only be seen through a microscope. Citrus canker is caused by bacteria and transmitted through air. (c) algae Question 34. Answer: a. Yeast reproduces asexually by the budding method. Question 19. Rust of wheat is a fungal disease spread through air. 618 Bacteria cause the decay of dead plants and animals. Dear Question 2. Bhendi yellow vein mosaic disease is caused by a virus and is spread by insects in lady fingers. Answer: Question 23. (iii) (b) Vaccine is prepared from weak or dead disease-causing microbe. (Also, refer Q. Fungi like yeast is used in bread, beer and wine. (iii) growth of yeast cells They can prevent the bacterial cells from multiplying so that the bacterial population remains the same, allowing the host’s defence mechanism to fight the infection or kill the bacteria, for example stopping the mechanism responsible for building their cell walls. Observe them after 3-4 weeks. Answer: Question 3. All the questions have four option with one option correct. How are dry fruits preserved ? Give the methods of prevention of cholera. It is important to take antibiotic only on the advice of a qualified doctor. Write 10 lines on the usefulness of microorganisms in our lives. Varicella zoster. It is observed that some tiny organisms are moving around. Answer: Write three types of bacteria on the basis of their shape. (iii) hydrochloric acid (c) direct contact (d) chappatis How are bacteria beneficial for us ? Answer: (b) virus [NCT 2006] Two diseases caused by bacteria are tuberculosis and diphtheria. (a), Question 9. Draw a labelled diagram of Rhizopus. Name two diseases caused by viruses. Chicken pox is caused by ………. Answer: Answer: Solution: Answer: Draw a neat and well-labelled diagram of Spirogyra. Answer: Antibiotics are effective in curing bacterial and fungal infections (e.g. (i) heat gal bat kar koi from punjab vase menu koi question ni tu dass je hege kyonki tu dass kdona ta munda... What are weeds? Answer: Answer: (c) drying virus. Others cannot be seen without the help of a microscope. Answer: Question 9. Polio. (b) using chemical preservatives Question: Write a short paragraph on the harms caused by microorganisms. Answer: Points, 13 (ii) housefly Question 1. Question 1. 8. What is a vaccine ? Question 15. Please choose a valid Answer: Question 14. Points, The source of these medicines is microorganisms. Tuberculin toxin is released by T.B. Bacteria are also involved in the making of cheese. (a) microscope Pathogens or germs enter a healthy body through air, water, contaminated food and infected person by direct or indirect contact or by the carrier. [KVS 2008] Yeast is used to prepare bread and alcohol. (iii) fermentation These … Question 7. (d) rabies Take a few drops of water from a pond. (a) virus There are for example numerous β-lactams (pronounced beta-lactams) such as different penicillins and [NCERT] They should not be taken unnecessarly because they will kill the useful bacteria. Answer: Blog | Points. What are pathogens ? 99 Very Short Answer Questions Define the term fermentation. Answer: Answer: Question 12. Antimicrobial is a group which also includes anti-parasitic, anti-fungal and anti-viral drugs. The invader their size into four major groups us as: Question 3 plant waste in pot.!: plant diseases can be seen with the help of a qualified doctor this of... Against them the causative microorganism of tuberculosis and its mode of transmission persons... 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