ainfoera.com – MCQs, Mock Tests | Biology Biology MCQS[NEET-2021 to 2022]-Microorganisms

1 ï»¿What is true about Archaebacteria?

A All fossils B All photosynthetic C All Halophiles D Oldest living beings

✅ Correct Answer: 4

2 The Ti plasmid is often used for making transgenic plants. This plasmid is found in

A Yeast as a 2 &#956;m plasmid B Agrobacterium C Rhizobium of the roots of leguminous plants D Azotobacter

✅ Correct Answer: 2

3 Reproduction in most of the bacteria is by a process known as

A Binary fission B Sexual C Sporulation D Budding

✅ Correct Answer: 1

4 An example of endomycorrhizal is

A Agaricus B Glomus C Nostoc D Rhizobium

✅ Correct Answer: 2

5 Human insulin is being commercially produced from a transgenic species of

A Escherichia B Saccharomyces C Rhizobium D Mycobacterium

✅ Correct Answer: 1

6 Specialized cells called heterocysts are present in

A Dinoflagellates B Euglenoids C Cyanobacteria D Archaebacteria

✅ Correct Answer: 3

7 The Gram negative bacteria detect and respond to chemicals in their surrounding by

A Lipopolysaccharide B Muramic acid C Porins D Volutin granules

✅ Correct Answer: 3

8 Which of the following protects the bacteria from the enzymes present in the external medium?

A Flagella B S-layer C Slime layer D Cell wall

✅ Correct Answer: 2

9 A bacterium is capable of withstanding extreme heat, dryness and toxic chemicals. This indicates that it is probably above to form

A Endotoxins B Endospores C A thick peptidoglycan wall D Endogenous buds

✅ Correct Answer: 2

10 Which one of the following is correct about Cosmid?

A Extra genetic material in mycoplasma B Circular DNA found in bacteria C Extra DNA in bacteria D Fragment of DNA inserted in bacteria for forming copies

✅ Correct Answer: 4

11 Which of the following groups of organisms are ecologically similar?

A Consumer protists and fungi B Monerans and producer protists C Producer protists and consumer protists D Monerans and fungi

✅ Correct Answer: 4

12 A bacterium which is capable of utilizing the most abundantly available gas in the atmosphere for one of its metabolic pathways, but cannot utilize the second most abundantly available for its another

A Azotobacter B Clostridium C Rhodomicrobium D Xanthomonas

✅ Correct Answer: 2

13 Identify the correct pair of events when temperate phages infect bacteria : (I) No prophages are formed. (II) Bacterial cell undergoes many divisions (III) Bacterial cell undergoes immediate lysis

A II, III B I, II C III, IV D II, IV

✅ Correct Answer: 4

14 Which type of DNA is found in bacteria?

A Helical DNA B Membrane bound DNA C Straight DNA D Circular free DNA

✅ Correct Answer: 4

15 Plasmids are most often found in

A Virus B Fungi C Bacteria D Viroid

✅ Correct Answer: 3

16 Cell wall of Gram positive bacteria is made up of

A Murein B Cellulose C Lipid and protein D Cellulose and lipid

✅ Correct Answer: 1

17 Bacteria with flagella all over the body is

A Peritrichous B Monotrichous C Amphitrichous D None of the above

✅ Correct Answer: 1

18 Which of the following is a free living nitrogen fixing bacterium present in the soil?

A Azotobacter B Rhizobium C Nitrosomonas D Pseudomonas

✅ Correct Answer: 1

19 An example for symbiotic bacteria

A Xanthomonas campestris B Rhizobium leguminosarum C Agrobacterium tumefaciens D Erwinia amylovora

✅ Correct Answer: 2

20 The asexual spores formed by Colletotrichum falcatum, Sphaerotheca and Rhizopus stolonifer are

A Many celled B Rod shaped C One celled D None of the above

✅ Correct Answer: 3

21 The bacterium (Clostridium botulinum) that causes botulism is

A A facultative aerobe B An obligate anaerobe C A facultative anaerobe D An obligate aerobe

✅ Correct Answer: 2

22 Red rot disease of sugarcane is caused by

A Colletotrichum falcatum B Helminthosporium oryzae C Xanthomonas D Phytophthora infestans

✅ Correct Answer: 1

23 Certain bacteria living in the soil poor in oxygen, convert nitrates into nitrites and then to free nitrogen and such bacteria are termed as

A Nitrogen fixing bacteria B Denitrifying bacteria C Ammonifying bacteria D Saprophytic bacteria

✅ Correct Answer: 2

24 Chromosomes in a bacterial cell can be 1 - 3 in number and

A can be either circular or linear, but never both within the same cell B can be circular as well as linear within the same cell C are always linear D are always circular

✅ Correct Answer: 4

25 N-acetylmuramic acid is found in

A Cell wall component of plant B Cell wall component of Gram positive bacteria C Cell wall component of fungi D Viral coat material

✅ Correct Answer: 2

26 dsRNA is found in

A Influenza virus B Retrovirus C Reovirus D TMP

✅ Correct Answer: 3

27 Which one of the followings is a viral disease?

A Wilting of cabbage B Red rot of sugar cane C Leaf roll of potato D Damping-off disease of seedlings

✅ Correct Answer: 3

28 Cauliflower mosaic virus contains

A ds DNA B ds RNA C ss RNA D ss DNA

✅ Correct Answer: 1

29 ELISA is used to detect viruses where the key reagent is

A DNA probe B Catalase C Alkaline phosphatase D RNase

✅ Correct Answer: 3

30 Due to discovery of which of the following in 1980, the evolution was termed as RNA world

A In some virus RNA is genetic material B RNA have enzymatic property C m-RNA, t-RNA- r-RNA synthesize proteins D RNA is not found in all cells

✅ Correct Answer: 2

31 Tailed bacteriophages are

A Motile on surface of bacteria B Motile on surface of plant leaves C Actively motile in water D Non-motile

✅ Correct Answer: 4

32 One important characteristic of viruses is that they

A Have an independent metabolism B Can be cultured in a cell-free medium C Can multiply outside a living cell D Do not have an independent metabolism

✅ Correct Answer: 4

33 Virus are living, because

A Carry metabolic activity B Carry anaerobic respiration C Multiply in host cells D Cause infection

✅ Correct Answer: 3

34 DNA is not present in one of the following

A Bacteriophage B Tobacco Mosaic Virus C Chloroplast D Mitochondria

✅ Correct Answer: 2

35 Which of the following statements is not true for retroviruses?

A Retroviruses are causative agents for certain kinds of cancer in man B The genetic material in mature retroviruses is RNA C Retroviruses carry gene for RNA-dependent DNA polymerase D DNA is not present at any stage in the life cycle of retroviruses.

✅ Correct Answer: 4

36 Viruses are no more "alive" than isolated chromosomes because

A They both require oxygen for respiration B They both need food molecules C They require both RNA and DNA D Both require the environment of a cell to replicate

✅ Correct Answer: 4

37 Which statement is correct for bacterial transduction?

A Transfer of some genes from one bacteria to another bacteria through virus B Bacteria obtained DNA from other external source C Bacteria obtained its DNA directly D None of the above

✅ Correct Answer: 1

38 Which of the following statements is true about viruses?

A All viruses known to man are obligate parasites B Viruses are capable of performing metabolic activities on their own C Viruses are filterable facultative parasites D Some viruses have cellular structure and are saprophytes

✅ Correct Answer: 1

39 How does enveloped virus enter into host cells?

A by injecting its own nucleic acid inside the host cells B by phagocytosis C by contact with ceil receptor and endocytosis D None of the above

✅ Correct Answer: 4

40 The genetic material in virus is

A DNA and RNA B DNA C DNA or RNA D RNA

✅ Correct Answer: 3

41 Protein coat of a virus enclosing nucleic acid is called

A Vector B Capsid C Plasmid D Genome

✅ Correct Answer: 2

42 The Phages that show lysogenic cycle are called

A Virulent phages B Lytic phages C Temperate phages D None of the above

✅ Correct Answer: 3

43 Which one of the following enzymes is present in the bacteriophage?

A Succinic dehydrogenase B Lysozyme C Protease D Urease

✅ Correct Answer: 2

44 Which one of the following viruses contains both DNA and RNA?

A Cyanophage B Herpes Virus C Polio Virus D Leuko Virus

✅ Correct Answer: 4

45 Bacteriophages kill

A Fungi B Parasites C Bacteria D Viruses

✅ Correct Answer: 3

46 Virus multiplies in

A living tissue B soil C dead tissue D culture medium

✅ Correct Answer: 1

47 Provirus is _____.

A free virus B free DNA C primitive virus D integrated viral genome

✅ Correct Answer: 4

48 The non-living characteristic of viruses is

A ability to undergo mutation B ability to multiply only inside the host C ability to cause diseases in the host D ability to be crystallized

✅ Correct Answer: 4

49 A T-series bacteriophage can be recognized by its

A irregular shape B rounded shape C tadpole shape D rhomboidal shape

✅ Correct Answer: 3

50 In AIDS, HIV kills

A Bone-Marrow cells B Antibody molecule C T-Helper cell D T-Cytotoxic cell

✅ Correct Answer: 3

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Biology MCQS[NEET-2021 to 2022]-Microorganisms