Explore topic-wise MCQs in Microbiology.

This section includes 128 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.

51.

To a living organism, which of the following has the greatest amount of available energy per molecule?

A. ATP
B. ADP
C. AMP
D. H2O
Answer» B. ADP
52.

An exergonic reaction is one that

A. requires energy to proceed
B. releases energy for work
C. gives off much heat
D. looses energy
Answer» C. gives off much heat
53.

If the free energy change (ΔG) in a reaction is a negative value, it indicates that the

A. reaction releases energy
B. reaction absorbs energy
C. reaction is in negative direction
D. reaction is in positive direction
Answer» B. reaction absorbs energy
54.

Which of the following statements is false regarding B cells?

A. B cells can undergo class switching and produce a different antibody type
B. B one marrow stem cells migrate to the thymus and develop into B cells
C. B cells synthesize antibodies and put them on their cell surface
D. B cells that recognize high concentrations of antigens (self) in the absence of other signals undergo apoptosis in the bone marrow
Answer» C. B cells synthesize antibodies and put them on their cell surface
55.

The role of the M cell is to

A. trap virus in mucus and prevent entry
B. induce apoptosis in virus-infected small intestinal epithelia cells
C. pass bacteria or virus to underlying macrophages for processing and presentation of antigen
D. they use their cilia to propel mucus out of the small intestine
Answer» D. they use their cilia to propel mucus out of the small intestine
56.

Macrophages are professional antigen- presenting cells. The protein molecule through which they present antigen in human is

A. actin
B. interleukin
C. HLA
D. CD8
Answer» E.
57.

Immunity is not long lasting to

A. influenza
B. whooping cough
C. diphtheria
D. mumps
Answer» B. whooping cough
58.

Which of the following(s) is/are the determinants of antigenicity?

A. Chemical nature
B. Size of the antigen
C. Foreignness
D. All of these
Answer» E.
59.

Following are the defenses of the colon except

A. sIgA
B. fast flow rate
C. dense resident microbiota
D. mucus
Answer» C. dense resident microbiota
60.

Natural killer cells are involved in

A. tumour rejection
B. allograft rejection
C. non-specific killing of virus transformed target cells
D. all of these
Answer» E.
61.

Quellung reaction is used for typing of

A. Klebsiella pneumoniae
B. Streptococcus pneumoniae
C. Both (a) and (b)
D. None of these
Answer» D. None of these
62.

Ring test is used for

A. C-reactive protein test
B. Ascoli's thermoprecipitation test
C. typing of streptococci and pneumococci
D. all of the above
Answer» E.
63.

Commercially available ELISA kits are used for the detection of

A. rotavirus
B. hepatitis B surface antigen
C. anti-HIV antibodies
D. all of these
Answer» E.
64.

Precipitation reaction can be converted into agglutination reaction by coating soluble antigen onto

A. bentonite particles
B. RBCs
C. latex particles
D. all of these
Answer» E.
65.

Weil-Felix reaction is based on sharing of antigens between

A. sheep RBCs and EB virus
B. mycoplasma and human O group RBCs
C. rickettsial antigens and antigens of certain strains of Proteus
D. none of these
Answer» D. none of these
66.

If the Keq for an enzymatic reaction is greater than 1, the reaction

A. will be endergonic
B. can not occur without the input of energy
C. both (a) and (b)
D. none of these
Answer» E.
67.

An endergonic reaction is one that

A. requires energy in order to proceed
B. releases energy for work
C. gives off much heat
D. looses energy
Answer» B. releases energy for work
68.

The ability of a competitive inhibitor to bind to an active site in an allosterically controlled enzyme is __________ than the ability of a non-competitive inhibitor to bind to an active site in the same allosterically controlled enzyme.

A. greater
B. lesser
C. approximately equal
D. half
Answer» B. lesser
69.

The ability of FADH to be oxidized is __________ than the ability of FAD to be oxidized.

A. greater
B. lesser
C. approximately equal
D. half
Answer» B. lesser
70.

Which is not an antigen-presenting cell (or APC)?

A. B cell
B. Polymorphonuclear leukocyte (or PMN)
C. Dendritic cell
D. All of the above
Answer» C. Dendritic cell
71.

Amount of various immunoglobulin classes can be measured by

A. double diffusion in one dimension
B. single diffusion in two dimensions
C. single diffusion in one dimension
D. double diffusion in two dimensions
Answer» C. single diffusion in one dimension
72.

In transport, hemophilia refers to failure to form

A. soluble proteins
B. insoluble proteins
C. phagocytes
D. heparin
Answer» C. phagocytes
73.

Counter-immunoelectrophoresis is used for the detection of

A. Meningococcal antigen
B. Hepatitis B surface antigen
C. Alpha-fetoprotein
D. All of these
Answer» E.
74.

Fluorescent treponemal antibody test is an example of

A. indirect immunofluorescence
B. direct immunofluorescence
C. both (a) and (b)
D. none of these
Answer» B. direct immunofluorescence
75.

Cytotoxic T-cells can be recognized by which of the following cell surface marker?

A. CD4
B. CD7
C. CD8
D. CD9
Answer» D. CD9
76.

Enzyme released upon injury to blood vessel is

A. thrombin
B. fibrinogen
C. thrombokinase
D. phagocyte
Answer» D. phagocyte
77.

Method(s) that can be used to detect CMI is/are

A. migration inhibition
B. target cell destruction factor test
C. skin test for delayed hypersensitivity
D. all of the above
Answer» E.
78.

J chain is present in

A. IgA
B. IgM
C. Both (a) and (b)
D. IgE
Answer» D. IgE
79.

Lens antigens of the eye are

A. cross-reacting antigens
B. sequestrated antigens
C. neoantigens
D. none of these
Answer» C. neoantigens
80.

Hemophilia refers to

A. blood deficiency
B. failure of blood clotting
C. a disturbance in bone marrow
D. excess of thrombokinase
Answer» C. a disturbance in bone marrow
81.

Anthranilate synthase, the first enzyme of tryptophan biosynthesis after the branch point shows feedback inhibition and repression due to

A. L-tryptophan
B. D-L-tryptophan hydantoin
C. L-serine
D. pyruvate
Answer» B. D-L-tryptophan hydantoin
82.

The term Agglutination refers to

A. clumping of bacteria together
B. easy attack by the antitoxins
C. eating of phagocytes
D. formation of pus
Answer» B. easy attack by the antitoxins
83.

Precipitation reaction is relatively less sensitive for the detection of

A. antigens
B. antigen-antibody complexes
C. antibodies
D. complement
Answer» D. complement
84.

A substrate binds to its enzyme at a location called the __________ site.

A. coenzyme
B. substrate
C. active
D. polypeptide
Answer» D. polypeptide
85.

Antigen binding sites of an immunoglobulin are located in

A. light chain alone
B. heavy chain alone
C. Fc region of the antibody
D. Fab regions of the antibody
Answer» E.
86.

'Stavudine' is drug that inhibit synthesis of

A. RNA
B. DNA
C. Proteins
D. Peptides
Answer» C. Proteins
87.

In transportation in mammals, Thrombokinase is

A. released during cellular respiration
B. helps building new protoplasm
C. released by damaged blood vessels
D. form of calcium ion
Answer» D. form of calcium ion
88.

Main side effect of drug 'ganciclovir' includes leukopenia and

A. Thrombocytopenia
B. Disk slip
C. Lock jaw
D. Gout
Answer» B. Disk slip
89.

'Ganciclovir' is an effective treatment against

A. Conjunctivitis
B. Retinitis
C. Bronchitis
D. Cancer
Answer» C. Bronchitis
90.

Chemically an antigen may be

A. lipid
B. protein
C. polysaccharide
D. any of these
Answer» E.
91.

Lysozyme is present in

A. sweat
B. Cerebro spinal fluid (CSF)
C. urine
D. saliva
Answer» E.
92.

Monoclonal antibody production requires

A. mouse splenic lymphocytes
B. mouse myeloma cells
C. both (a) and (b)
D. none of these
Answer» D. none of these
93.

Toxins induce blood to produce

A. antitoxins
B. phagocytes
C. platelets
D. monocytes
Answer» B. phagocytes
94.

Agglutination reaction is more sensitive than precipitation for the detection of

A. antigens
B. antibodies
C. complement
D. antigen-antibody complexes
Answer» B. antibodies
95.

Slide agglutination reaction is/are useful for the identification of the culture(s) of

A. Shigella
B. Vibrio cholerae
C. Salmonella
D. All of these
Answer» E.
96.

Which of the following (s) is/are function (s) of Fc fragment of IgG?

A. It determines catabolic rate
B. It binds complement
C. It is related to passage of IgG across the placental barrier
D. All of these
Answer» E.
97.

Denaturation of an enzyme refers to the

A. improper arrangement of the enzyme in a metabolic pathway
B. loss of the enzymes proper shape
C. formation of the enzymes proper shape
D. formation of a new isozyme for that enzyme
Answer» C. formation of the enzymes proper shape
98.

'Entecavir' is a

A. Guanosine analogue
B. Cytosine analogue
C. Thymine analogue
D. Alanine analogue
Answer» B. Cytosine analogue
99.

Neisseria gonorrhoeae, Treponema pallidum and chlamydia trachomatis are isolated from the

A. Urine culture
B. Genital tract culture
C. Sputum culture
D. Stool culture
Answer» C. Sputum culture
100.

An important phagocytes, responses to inflammation, included 'macrophages' and

A. Neutrophils
B. Basophils
C. Histamine
D. Bradykinin
Answer» B. Basophils