Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

Microaerophilic bacteria require low levels of oxygen for growth.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
2.

Mesophiles are group of bacteria that grow within the temperature range of?

A. 0-20 degree Celsius
B. 25-40 degree Celsius
C. 45-60 degree Celsius
D. more than 60 degree Celsius
Answer» C. 45-60 degree Celsius
3.

A piece of DNA, having ability to move from one site to another, either between DNA's of plasmids, bacterias, bacteriophages or within DNA molecule, is called

A. Vector
B. Transposons
C. Plasmid
D. Template
Answer» C. Plasmid
4.

In which of the following, lipo-polysaccharide is a major constituent of outer membrane of the cellwall?

A. Gram-positive bacteria
B. Gram-negative bacteria
C. Fungi
D. None of these
Answer» C. Fungi
5.

Which of the following is a rich source of B vitamins?

A. Peptone
B. Yeast extract
C. Beef extract
D. Agar
Answer» C. Beef extract
6.

Which of the following is not true about peptidoglycan?

A. It is a polymer consisting of N-acetyl glucosamine, N-acetyl muramic acid and amino acids (alanine, lysine, etc.)
B. It is present in prokaryotic cell wall
C. It occurs in the form of a bag shaped macro molecule surrounding the cytoplasm membrane
D. None of the above
Answer» E.
7.

In eukaryotic cells, ribosomes are

A. 70S
B. 60S
C. 80S
D. Not specific
Answer» D. Not specific
8.

In the growth equation: n= 3.3 (log10 N – log10 No ), n stands for____________

A. total population
B. initial population
C. number of generations
D. growth constant
Answer» D. growth constant
9.

Which of the following is used as a solidifying agent for media?

A. Beef extract
B. Peptone
C. Agar
D. Yeast extract
Answer» D. Yeast extract
10.

Name the component of flagellum.

A. Filament
B. Hook
C. Basal body
D. All of these
Answer» E.
11.

What is approximate number of genes in human in contrast to 'prokaryotes' ?

A. 100000
B. 1000000
C. 10000
D. 200000
Answer» B. 1000000
12.

Which of the following structure(s) is /are external to cell wall?

A. Flagella
B. Stalks
C. Sheath
D. All of these
Answer» E.
13.

Site for nutrients in 'cytoplasm' is

A. Vacuole
B. Food vacuole
C. Granules
D. Cytosol
Answer» D. Cytosol
14.

Which of the following is used to grow bacterial culture continuously?

A. Chemostat
B. Hemostat
C. Coulter-Counter
D. Turbidostat
Answer» B. Hemostat
15.

Which of the following ROS is a powerful oxidizing agent?

A. Superoxide radical
B. Hydrogen peroxide
C. Hydroxyl radical
D. Singlet oxygen
Answer» C. Hydroxyl radical
16.

A bleb or fold like formation occurs in which of the following bacteria?

A. Rhodopseudomonas acidophila
B. Bacillus subtilis
C. E.coli
D. Streptococcus faecalis
Answer» D. Streptococcus faecalis
17.

The synthesis of new membrane material during reproduction in Gram-positive cells is performed by which of the following organelles?

A. Nucleus
B. Mesosome
C. Endoplasmic Reticulum
D. Cytoplasmic membrane
Answer» C. Endoplasmic Reticulum
18.

Equatorial ridge formation in the cell wall takes place in which of the following bacteria?

A. Streptomyces sp.
B. Bacillus subtilis
C. Streptococcus faecalis
D. Escherichia coli
Answer» D. Escherichia coli
19.

The Reactive Oxygen Species(ROS) poduced by some bacteria are degraded by which of the following enzymes?

A. Peroxidase
B. Lyase
C. Catalase
D. Superoxide dismutase, Catalase and Peroxidase
Answer» E.
20.

Transverse binary fission requires the formation of a crosswall.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
21.

Bacteria having no flagella are unable to

A. move
B. reproduce
C. stick to tissue surfaces
D. grow in nutrient agar
Answer» B. reproduce
22.

The last step in synthesis of peptidoglycan is

A. attachment of a peptide to muramic acid
B. attaching two amino acids to form a cross-link
C. attachment of a portion of peptidoglycan to a membrane lipid
D. binding of penicillin to a membrane protein
Answer» C. attachment of a portion of peptidoglycan to a membrane lipid
23.

The bacterium Staphylococcus aureus is which type of bacteria?

A. Psychrophile
B. Mesophile
C. Thermophile
D. Mesophile and psychrophile
Answer» C. Thermophile
24.

Which is most likely to be exposed on the surface of a gram-negative bacterium?

A. Pore protein (porin)
B. Protein involved in energy generation
C. Lipoteichoic acid
D. Phospholipids
Answer» B. Protein involved in energy generation
25.

The cooci which mostly occur in single or pairs are

A. Streptococci
B. Diplococci
C. Tetracocci
D. None of these
Answer» C. Tetracocci
26.

A cluster of polar flagella is called

A. lophotrichous
B. amphitrichous
C. monotrichous
D. petritrichous
Answer» B. amphitrichous
27.

Which of the following are functions of phosphates used in the preparation of media?

A. they act as buffer
B. source of phosphorous
C. act as “reserve alkali”
D. they act as buffer and is a source of phosphorous
Answer» E.
28.

Which of the following is true about cell wall of gram-positive bacteria?

A. It consists of multiple layers
B. It is thicker than that associated with gram-negative bacteria
C. It contains teichoic acids
D. All of these
Answer» E.
29.

Which of the following are functions of Maintenance Media?

A. used for assay of vitamins,amino acids
B. used for determining the bacterial content
C. used for determining the type of growth produced by bacteria
D. used for the maintenance of the viability and physiological characteristics
Answer» E.
30.

The other name for peptidoglycan is

A. mucopeptide
B. murein
C. both (a) and (b)
D. none of these
Answer» D. none of these
31.

Circular, double-stranded and extrachromosomal DNA, can replicate independently of bacterial chromosome, called as

A. Plasmid
B. Cosmic
C. Vector
D. Template
Answer» B. Cosmic
32.

Colony formation can be observed in liquid media broth.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
33.

Which of the following bacteria requires nicotinic acid as a growth factor in their media?

A. Proteus vulgaris
B. Nitrosomonas sp.
C. E. coli
D. Leuconostoc mesenteroides
Answer» B. Nitrosomonas sp.
34.

The optimum pH for the growth of most bacteria lies between_______

A. 5-9
B. 6.5-7.5
C. 2-3.5
D. 9-9.5
Answer» C. 2-3.5
35.

Peptidoglycan is found only in the bacterial

A. cell membrane
B. glycocalyx
C. cell wall
D. spore
Answer» D. spore
36.

The endoflagella is present in which class of bacteria?

A. Spirilla
B. Spirochetes
C. Bacillus
D. Coccus
Answer» C. Bacillus
37.

Where is the endoflagella located in Spirochetes?

A. In the cell membrane
B. In the cytoplasm
C. In the peptidoglycan layer
D. In the periplasmic space
Answer» E.
38.

Spirochetes like other bacteria swim best in media of low viscosity.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
39.

Which of the following methods is used for viewing spirochetes?

A. Bright-field microscopy
B. Phase-contrast microscopy
C. Dark-field microscopy
D. Electron microscopy
Answer» D. Electron microscopy
40.

The family Leptospiraceae are aerobes.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
41.

Which of the following bacteria lack a cell wall and are therefore resistant to penicillin?

A. Cyanobacteria
B. Mycoplasmas
C. Bdellovibrios
D. Spirochetes
Answer» C. Bdellovibrios
42.

Which of the following instrument is used for sterilizing the media after it has been prepared?

A. Autoclave
B. Laminar Air Flow Chamber
C. Inoculum Needle
D. Incubator
Answer» B. Laminar Air Flow Chamber
43.

Which of the following may contain fimbriae?

A. Gram-positive bacteria
B. Gram-negative bacteria
C. Both (a) and (b)
D. None of these
Answer» C. Both (a) and (b)
44.

Endotoxin is present in outer membrane of cell wall of gram-negative bacteria, known as

A. Polysaccharides
B. Lipopolysaccharides
C. Sugars
D. Lipid
Answer» C. Sugars
45.

Growth of bacteria or microorganisms refer to __________________

A. an increase in the size of an individual organism
B. an increase in the mass of an individual organism
C. changes in the total population
D. an increase in number of cells
Answer» E.
46.

Cytoplasmic inclusions include

A. ribosomes
B. mesosomes
C. fat globules
D. all of these
Answer» E.
47.

Lag phase is also known as ___________

A. period of initial adjustment
B. transitional period
C. generation time
D. period of rapid growth
Answer» B. transitional period
48.

Periplasm is

A. the area between the inner and outer membranes of gram-negative bacteria
B. the area between the inner and outer membranes of Gram-positive bacteria
C. the interior portion of mitochondria
D. the area outside the cell membrane that is influenced by the polymers
Answer» B. the area between the inner and outer membranes of Gram-positive bacteria
49.

Pleomorphic' is term used particularly for bacteria, havng

A. One shape
B. Rods
C. Spirals
D. Variable shape
Answer» E.
50.

Swimming towards a chemical of bacteria is termed as

A. positive chemotaxis
B. negative chemotaxis
C. phototaxis
D. magnetotaxis
Answer» B. negative chemotaxis