Useful and Harmful Microbes
Q1. What are microbes?
A. Microbes are microscopic living organisms that cannot be seen with the naked eye.
Q2. Name four major types of microbes.
A. Bacteria, Viruses, Fungi, Protozoa.
Q3. Name one microbe used in the production of antibiotics.
A. Penicillium notatum.
Q4. Who discovered penicillin?
A. Alexander Fleming in 1928.
Q5. Name one microbe used in alcohol production.
A. Yeast (Saccharomyces cerevisiae).
Q6. Which bacteria is used in curd formation?
A. Lactobacillus.
Q7. Name one microbe used in the production of vitamin B12.
A. Propionibacterium shermanii.
Q8. What is biological nitrogen fixation?
A. The process by which certain microbes convert atmospheric nitrogen into usable forms for plants.
Q9. Name one nitrogen-fixing bacteria in root nodules.
A. Rhizobium.
Q10. Name one free-living nitrogen-fixing bacteria.
A. Azotobacter.
Q11. Give one example of microbes used in sewage treatment.
A. Methanogens like Methanobacterium.
Q12. Name one microbe used in antibiotics other than Penicillium.
A. Streptomyces for streptomycin.
Q13. Which microbe causes tuberculosis?
A. Mycobacterium tuberculosis.
Q14. Which microbe causes typhoid?
A. Salmonella typhi.
Q15. Name the virus causing AIDS.
A. Human Immunodeficiency Virus (HIV).
Q16. Which microbe causes malaria?
A. Plasmodium species (protozoa).
Q17. Which fungus causes ringworm?
A. Trichophyton.
Q18. Name one bacterial disease in plants.
A. Citrus canker.
Q19. Name one fungal disease in plants.
A. Rust of wheat.
Q20. Name one viral disease in plants.
A. Tobacco Mosaic Virus (TMV).
Q21. How do microbes help in digestion in humans?
A. Gut microbes help in breaking down complex food substances and synthesizing vitamins.
Q22. How do microbes help in cheese production?
A. Certain bacteria and fungi are used to ripen cheese and give it flavour.
Q23. Give one example of microbe used in organic farming.
A. Blue-green algae like Anabaena.
Q24. What is bio-control?
A. Using living organisms, including microbes, to control pests and diseases.
Q25. Give an example of bio-control microbe.
A. Bacillus thuringiensis (Bt).
Q26. How do microbes help in biogas production?
A. Anaerobic bacteria break down organic waste to produce methane gas.
Q27. What are probiotics?
A. Live beneficial microbes that promote health when consumed.
Q28. Name one probiotic microbe.
A. Lactobacillus acidophilus.
Q29. How do microbes spoil food?
A. By growing on food and producing toxins or unpleasant odours and tastes.
Q30. How can we prevent diseases caused by harmful microbes?
A. By maintaining hygiene, proper cooking of food, vaccination, and safe drinking water.