Microbes in Human Welfare Class 12 MCQs Questions with Answers

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

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

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

4. Methanogens do not produce

5. Bacillus thuringiensis is used to control

6. Term antibiotic was first used by :

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

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

9. Azoila has symbiotic relationship with:

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

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

12. Process of biogas production is

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

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

15. Usnic acid is an antibiotic obtained from :

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

17. Citric acid is produced by:

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

19. Lactic acid is formed by the process of

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