Question

Any 7 questions please Answer!!!!

13. Why must media, vessels and instruments be sterilized before they are used for microbiological procedures?

14. What is the difference between complex media and defined media? Give one example of each.

15. Why is it necessary to use strong disinfectants in areas exposed to tuberculosis patients?

16. Describe five physical methods of microbial growth.

17. Contrast the structures and actions of soaps and quats.

18 How do halogens control microbial growth? Compare and contrast the use of iodine and chlorine.

19. Why is autoclaving true sterilization and boiling is effective for sanitizing restaurant tableware?

20. Compare and contrast incineration and hot air as examples of dry heat used to control microbial growth.

21. How does mitosis differ from binary fission?

22. Why are they more antibacterial drugs than antifungal drugs?

23. How are the cysts of protozoan similar to endospores and how do they differ?

24. Alveolates are divided into three subgroups, list the groups and describe one example for each subgroup.

25. What is a schizont? What pathogen reproduce asexually via schizogony?

Answer 1

13. Microbiological procedures are used for the growth of a specific type of microbial strain. So, all the quipments should be sterilized in advance so as to avoid contamination by any other undesirable microbe and which may interfere with the growth of the desired one.

14. Complex media can be defined as the one where its chemical constituents may vary; i.e the exact chemical composition is not known. It is also rich in nutrients. Ex: Nutrient Agar. Defined media is the one where its exact chemical composition is known and it remains constant for every batch culture. They are specifically suited for the in vitro cell culture. Ex: Glucose Salt Broth.

15. The cell membrane of the bacteria causing tuberculosis is characterised by the presence of waxy lipids which prevents them from dessication and drying out. So, strond disinfectants should be used so as to prevent contamination from the infected to the non infected ones.

21. Binary fission is a mode of division into daughter cells among prokaryotes. The cellular divison doesnot involve formation of spindle fibres and hence is a faster mode of division. Mitosis is characterised by the cell division occuring in eukaryotes. Commonly known as somatic division, it requires siter chromatids and mitotic apparatus for its division.

22. Bacteria are essentially prokaryotic and there are striking differences from eukaryotic organisms. On the other hand, fungi are eukaryotic organisms which share many of the characteristics with their host. So, it becomes all the more difficult to design drugs against them because there remains a probabaility that it might affect the host as well.

23. The cysts of protozoan are similar to endospores in the way that they are capable of surviving dessication. Endospores are actively living cells, they remain dormant in nature and used in times of unfavourable conditions. Whereas, cyst is a hard protective covering of the bacteria which are essentially non living in nature.

24. Schizonts are cells produced asexually by Plasmodium falciparum which consists of many merozoites. Pathogen reproduces asexually via schizogeny so as to keep them doramant in the liver of host which can be activated even after many years. The schizonts also serve as carrier of merozoites to the RBCs.