This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Biology Chapter 10 Microbes In Human Welfare – Quiz 5 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 5 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Statement I:The activated sludge is pumped into large tanks called anaerobic sludge digesters. Statement II:In these tanks, other kinds of bacteria, which grow anaerobically, digest the bacteria and fungi in the sludge. A) Both Statement I and Statement II are correct. B) Both Statement I and Statement II are incorrect. C) Statement I is correct, but Statement II is incorrect. D) Statement I is incorrect, but Statement II is correct. Show Answer Correct Answer: A) Both Statement I and Statement II are correct. 2. The dough used for making bread is fermented by A) Bacteria. B) Yeast. C) Fungi. D) Algae. Show Answer Correct Answer: B) Yeast. 3. IPM stands for A) Indian Pollution Management. B) Institute of Pest Management. C) Integrated Pest Management. D) Institute of Pollution Management. Show Answer Correct Answer: C) Integrated Pest Management. 4. A small part of the activated sludge is pumped back into the aeration tank to serve as: A) An energy source. B) An inoculum. C) A fertilizer. D) An aerator. Show Answer Correct Answer: B) An inoculum. 5. Assertion (A):Leguminous plants are best preferred in rotation of cropsReason(R):They have root nodules which have nitrogen fixing bacteria Clostridium. A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true But R is not correct explanation of A. C) A is true, but R is false. D) Both A and R are false. Show Answer Correct Answer: C) A is true, but R is false. 6. A typical biogas plant consists of a concrete tank in which bio-wastes are collected and a slurry of dung is fed. A ..... is placed over the slurry. A) Fixed steel lid. B) Floating cover. C) Mesh net. D) Aeration pipe. Show Answer Correct Answer: B) Floating cover. 7. A common nitrogen fixer in common fields is A) Nostoc. B) Azopirillum. C) Rhizobium. D) Oscillatoria. Show Answer Correct Answer: A) Nostoc. 8. Yeasts have been used for the commercial production of A. wineB. whiskyC. ethanolD. curd A) A, B, C. B) A, B, C, D. C) B, C, D. D) A, B, D. Show Answer Correct Answer: A) A, B, C. 9. Certain bacteria, which grow anaerobically on cellulosic material, produce large amounts of methane along with CO ..... 2 and H ..... 2. These bacteria are collectively called: A) Methylotrophs. B) Methanogens. C) Biogas bacteria. D) Rumen bacteria. Show Answer Correct Answer: B) Methanogens. 10. Trichoderma species are free-living fungi that are very common in: A) Leaves of fruit trees. B) Root ecosystems. C) Stems of brassicas. D) Digestive tracts of insects. Show Answer Correct Answer: B) Root ecosystems. 11. Acetic acid is produced by a: A) Fungus. B) Bacterium. C) Yeast. D) Virus. Show Answer Correct Answer: B) Bacterium. 12. The primary treatment of sewage involves- A) Digestion. B) Decomposition. C) Sedimentation and filtration. D) None of these. Show Answer Correct Answer: C) Sedimentation and filtration. 13. Process used in water treatment process where water is pushed through screens, sand, gravel and coal to remove organisms and trash A) Filtration. B) Chlorination. C) Coagulation. D) Bioreactors. Show Answer Correct Answer: A) Filtration. 14. Statins used for lowering blood-cholesterol level are extracted from: A) Algae. B) Bacteria. C) Virus. D) Yeast. Show Answer Correct Answer: D) Yeast. 15. During secondary treatment, vigorous growth of useful aerobic microbes into 'flocs' occurs. What are 'flocs'? A) Masses of bacteria associated with viral filaments. B) Masses of bacteria associated with fungal filaments to form mesh-like structures. C) Masses of algae and fungi. D) Sedimented pebbles and grit. Show Answer Correct Answer: B) Masses of bacteria associated with fungal filaments to form mesh-like structures. 16. Microbes like bacteria and many fungi can be grown on nutritive media to form colonies. These colonies are useful because: A) They are microscopic and can only be seen under a microscope. B) They allow the microbes to be seen with the naked eye. C) They produce large amounts of biogas immediately. D) They show the genetic structure of the virus. Show Answer Correct Answer: B) They allow the microbes to be seen with the naked eye. 17. In Gobart gas the maximum amount is that of A) Butane. B) Propane. C) Methane. D) Ethane. Show Answer Correct Answer: C) Methane. 18. Select the correct statement from the following A) Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria. B) Biogas is produced by the activity of aerobic bacteria on animal waste. C) Methanobacterium is an aerobic bacterium found in rumen of cattle. D) Biogas, commonly called gobar gas, is pure methane. Show Answer Correct Answer: A) Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria. 19. Which of the following bacteria has a role in removing clots from our blood vessels? A) Bacillus thuringiensis. B) Clostridium butylicum. C) Streptococcus. D) Lactobacillus. Show Answer Correct Answer: C) Streptococcus. 20. What happens in the digesters? A) Aerobic bacteria processes organic waste. B) Organic waste is turned into usable fertilizer. C) Anaerobic bacteria processes organic waste. D) Chlorine is added to disinfect biosolids. Show Answer Correct Answer: C) Anaerobic bacteria processes organic waste. 21. Lactic Acid Bacteria (LAB) improve the nutritional quality of curd by increasing the amount of: A) Vitamin C. B) Vitamin B12. C) Vitamin A. D) Proteins. Show Answer Correct Answer: B) Vitamin B12. 22. Which of the following serves as an important biofertilizer in paddy fields? A) Rhizobium. B) Blue Green Algae (Cyanobacteria). C) All the above. D) None of the above. Show Answer Correct Answer: B) Blue Green Algae (Cyanobacteria). 23. Which bacteria form symbiotic association with the nodules on the roots of leguminous plants to fix atmospheric nitrogen? A) Azospirillum. B) Azotobacter. C) Rhizobium. D) Anabaena. Show Answer Correct Answer: C) Rhizobium. 24. Identify the function of statin A) Removal of oil stains. B) Removal of clots from blood vessels. C) Lowering of blood cholesterol. D) Immuno-suppressive agent. Show Answer Correct Answer: C) Lowering of blood cholesterol. 25. The same yeast, Saccharomyces cerevisiae, is used for bread-making and beverage production. In the context of beverages, it is commonly called: A) Baker's yeast. B) Brewer's yeast. C) Distiller's yeast. D) Fermenter's yeast. Show Answer Correct Answer: B) Brewer's yeast. ← PreviousNext →Related QuizzesClass 12 Biology Chapter 10 Microbes In Human Welfare Quiz 1Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 2Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 3Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 4Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 6Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 7Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 8Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 9Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 10Class 12 Biology Chapter 10 Microbes In Human Welfare Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books