Microbes in Human Welfare Class 12 MCQs Questions with Answers

1. Which of the followings is mainly produced by the activity of anaerobic bacteria on sewage?

2. Usnic acid is an antibiotic obtained from :

3. Which of the following is widely used as a successful biofertiliser in Indian rice field ?

4. BOD of wastewater is estimated by measuring the amount of

5. The nutritive medium for growing bacteria and many fungi in laboratory is called

6. Process of biogas production is

7. Azoila has symbiotic relationship with:

8. Lactic acid is formed by the process of

9. Which one of the following is not a nitrogenfixing organism?

10. The residue left after methane production from cattle dung is

11. Methanogens do not produce

12. Term antibiotic was first used by :

13. Citric acid is produced by:

14. The chemical substances produced by some microbes which can kill or retard the growth of other microbes are called

15. During the primary treatment of sewage, solid particles that settle down are called

16. For retting of jute, the fermenting microbe is:

17. Which one of the following can be used as biofertiliser in cotton field ?

18. Bacillus thuringiensis is used to control

19. Which one of the following is not used in organic farming?

20. The vitamin whose content increases following the conversion of milk into curd by lactic acid bacteria is