Microbes in Human Welfare Class 12 MCQs Questions with Answers

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

2. Usnic acid is an antibiotic obtained from :

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

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

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

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

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

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

9. Lactic acid is formed by the process of

10. Term antibiotic was first used by :

11. Methanogens do not produce

12. Bacillus thuringiensis is used to control

13. Azoila has symbiotic relationship with:

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

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

16. Process of biogas production is

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

18. Citric acid is produced by:

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

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