Questions and Answers pdf
1. Extra nuclear DNA in E. coli is termed as
(a) F+ factor
(b) sex factor
(c) episome
(d) All of these
Ans. d
2. Smallest cell/organism is that of
(a) vibrio
(b) bacillus
(c) mycoplasma
(d) Rhizobium
Ans. c
3. Bacteria which retain purple colour after staining with Gram stain is
(a) Gram +ve
(b) Gram -ve
(c) trichous
(d) spirillum
Ans. a
4. Which of the following is a rod-shaped bacterium?
(a) Bacillus subtilis
(b) Pneumococcus pneumoniae
(c) Vibrio cholerae
(d) Streptococcus nigricans
Ans. a
5. Bacteria having a tuft of flagella at both ends are called
(a) peritrichous
(b) bitrichous
(c) amphitrichous
(d) atrichous
Ans. c
6. Bacteria which are smallest in size are
(a) cocci
(b) vibrio
(c) bacilli
(d) spirilla
Ans. a
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7. Bacteria, whose cells have only a single curve are known
(a) vibrio
(b) cocci
(c) spirilla
(d) bacilli
Ans. a
8. Non-photosynthetic, unicellular, cell wall bound spherical or rod-shaped microorganisms usually smaller than 5 micron in size which lack an organised nucleus are called
(a) viruses
(b) bacteria
(c) cyanobacteria
(d) mycoplasma
Ans. b
9. Organisms which have cell but no distinct nucleus are
(a) bacteria
(b) cyanobacteria
(c) Both (a) and (b)
(d) None of these
Ans. c
10. What does the bacterial cells possess in eukaryotic cells?
(a) Photosynthetic pigments
(b) A nucleoid with a circular chromosome
(c) Membrane-enclosed organelles
(d) A 9 + 2 arrangement of microtubules
Ans. b
11. Plasmids
(a) replicate independently of
(b) often contain antibiotic resistance genes
(c) are transferred from one bacterium to another by conjugation
(d) All of the above main chromosome
Ans. d
12. Bacteria were first discovered by (bacteria were for the first time observed by)
(a) A V Leeuwenhoek
(b) Robert Hooke
(c) Robert Koch
(d) Louis Pasteur
Ans. a
13. The largest non-sulphur bacteria are
(a) vibrio
(b) Bacillus subtilis
(c) spirillum
(d) E. coli
Ans. c
14. Staphylococcus bacterium is a
(a) chain-like colony
(b) plate-like colony
(c) bunch-like colony
(d) cube-like colony
Ans. c
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15. Which of the following is the size of bacteria?
(a) 2-10µ
(b) 10-15 µ
(c) 50-100µ
(d) 100-200 µ
Ans. a
16. A spherical bacterium is termed as
(a) vibrio
(b) coccus
(c) bacillus
(d) spirillum
Ans. b
17. What is the general shape of the Bacilli bacteria?
(a) Rod-shaped
(b) Spherical
(c) Spiral
(d) Comma
Ans. a
18. Bacteria having a tuft of flagella at one end are called
(a) peritrichous
(b) monotrichous
(c) lophotrichous
(d) amphitrichous
Ans. c
19. The smallest bacteria measure approximately
(a) 0.5u
(b) 0.05 u
(c) 0.005 u
(d) 0.0005 u
Ans. a
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20. Largest among sulphur bacteria are
(a) Chlorobium
(b) Beggiatoa
(c) Chromatium
(d) Thiobacillus
Ans. b
21. Bacteria differ from other plants in that they do not have
(a) DNA
(b) RNA
(c) cell wall
(d) a well-defined nucleus
Ans. d
22. Which one of the following does not follow the central dogma of molecular biology?
(a) HIV
(b) Pea
(c) Mucor
(d) Chlamydomonas
Ans. a
23. Infectious proteins are
(a) satellite viruses
(b) gemini viruses
(c) prions
(d) viroids
Ans. c
24. What is not true about retrovirus?
(a) DNA has no role in life cycle
(b) There is a gene for RNA dependent DNA polymerase
(c) Genetic material is RNA
(d) They are causative agents for certain cancers
Ans. d
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25. A chemical compound that is found in all viruses is
(a) Only RNA
(b) lipid
(c) RNA or DNA
(d) protein
Ans. c
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26. Bacteriophage kill
(a) fungi
(b) parasite
(c) bacteria
(d) viruses
Ans. c
27. Provirus is
(a) a free virus
(b) a primitive virus
(c) an integrated viral genome
(d) a free DNA
Ans. c
28. The process which cannot take place in the absence of virus is
(a) transformation
(b) conjugation
(c) translocation
(d) transduction
Ans. d
29. Which of the following is not a viral disease?
(a) AIDS
(b) Smallpox
(c) Tuberculosis
(d) Influenza
Ans. c
30. Which was the virus to be crystallised for the first time?
(a) Cauliflower mosaic virus
(b) Tobacco mosaic virus
(c) Tomato mosaic virus
(d) Influenza virus
Ans. b
31. Average size range of a virus is
(a) 10-30 nm
(b) 20-14,000 nm
(c) 100-1000 nm
(d) 1-10 nm
Ans. b
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32. The main difference between Gram positive and Gram negative bacteria is
(a) cell membrane
(b) cell wail
(c) ribosome
(d) mitochondria
Ans. b
33. Helically coiled-shaped bacteria are called
(a) spirilla
(b) cocci
(c) bacili
(d) vibrio
Ans. a
34. Extrachromosomal material of bacteria is found as
(a) circular DNA
(b) extrachromosomal DNA
(c) plasmid
(d) All of these
Ans. d
35. Bacteria pili are involved in
(a) asexual reproduction
(b) sexual reproduction
(c) saprophytic nutrition
(d) antibiotic resistance
Ans. b
36. One of the following bacteria is a good vector in genetic engineering.
(a) Mycobacterium tuberculosis
(b) Agrobacterium tumefaciens
(c) Salmonella typhimurium
(d) Bacillus amyloliquefaciens
Ans. b
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37. From where most of the antibiotics are extracted?
(a) Algae
(b) Bacteria
(c) Virus
(d) Plants
Ans. b
38. Mesosome in a bacterial cell is
(a) plasmid
(b) connection between two cells
(c) plasma membrane infolding for respiration
(d) None of the above
Ans. c
39. The wall of bacteria consists of
(a) N-acetyl glucosamine
(b) N-acetyl muramic acid
(c) Both (a) and (b)
(d) cellulose
Ans. c
Bacteria multiple choice questions and answers
40. Bacteria found in hot acidic aerobic conditions, are
(a) halophiles
(b) thermoacidophiles
(c) methanogens
(d) rickettsiae
Ans. b
41. Gram-negative bacteria that is not aerobic is
(a) Escherichia
(b) Pseudomonas
(c) Neisseria
(d) None of these
Ans. a
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42. Name the enzyme which hydrolyses murein
(a) peroxidase
(b) lysozyme
(c) tannase
(d) None of these
Ans. c
43. Coliform bacteria on fermentation of carbohydrates yields
(a) acetic acid
(b) lactic acid
(c) formic acid
(d) All of these
Ans. d
44. Protein from which hook and filaments of flagela are composed is
(a) keratin
(b) flagellin
(c) gelatin
(d) casein
Ans. b
45. Germ theory of diseases was putforth by
(a) Edward Jenner
(b) Weismann
(c) Louis Pasteur
(d) Robert Koch
Ans. c
