Microbes in Human Welfare Class 12 MCQs Questions with Answers

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

2. Azoila has symbiotic relationship with:

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

4. Lactic acid is formed by the process of

5. Methanogens do not produce

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

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

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

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

10. Bacillus thuringiensis is used to control

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

12. Process of biogas production is

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

14. Usnic acid is an antibiotic obtained from :

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

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

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

18. Term antibiotic was first used by :

19. Citric acid is produced by:

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