Explore topic-wise MCQs in Microbiology.

This section includes 195 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.

151.

The transfer of genes from one cell to another by a bacteriophage is known as __________________

A. Recombination
B. Conjugation
C. Transduction
D. Transformation
Answer» D. Transformation
152.

Which of the following is true about β-ionone, non-ionic detergent used in β carotene fermentation medium?

A. It is a precursor of β-carotene fermentation process
B. It is regarded as "steering" factor associated with bringing about the presence and activity of the enzymes responsible for β-carotene formation
C. It is an inducer of β carotene fermentation process
D. None of the above
Answer» C. It is an inducer of β carotene fermentation process
153.

In conjugation only small fragments of the bacterial chromosome are transferred.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
154.

Sickle cell anemia is which type of mutation?

A. nonsense mutation
B. missense mutation
C. deletion mutation
D. insertion mutation
Answer» C. deletion mutation
155.

Fungal amylases using stationary culture with wheat bran utilizes

A. A. oryzae
B. A. niger
C. A. flavus
D. S. cerevisiae
Answer» B. A. niger
156.

What is the frequency of formation of recombinants in a F+ X F— cross?

A. 100
B. 40
C. 10
D. 1
Answer» E.
157.

Which of the following is not a penicillin?

A. Penicillin G
B. Penicillin X
C. Penicillin V
D. Penicillin Y
Answer» E.
158.

The leavening or rising of dough is due to which of the following gases?

A. oxygen
B. carbon dioxide
C. hydrogen
D. sulphur dioxide
Answer» C. hydrogen
159.

Base analogs have the same hydrogen-bonding properties as the normal bases.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
160.

Which of the following organisms have shown the ability of phosphate solubilization in red wine?

A. S.cerevisiae
B. Gluconobacter oxydans
C. Bacillus subtilis
D. None of these
Answer» C. Bacillus subtilis
161.

During fermentation, pyruvic acid is converted into organic products such as

A. glucose and fructose
B. starch and cellulose
C. ethyl alcohol and lactic acid
D. citric acid and isocitric acid
Answer» D. citric acid and isocitric acid
162.

Which of the following agents involve biosensors linking with electronic circuit?

A. Microorganisms
B. Microbially derived enzymes
C. Either microorganisms or microbially derived enzymes
D. Neither microorganisms nor microbially derived enzymes
Answer» C. Either microorganisms or microbially derived enzymes
163.

The method used for obtaining citric acid as fermentation product are commonly known as

A. submerged aerated fermentation
B. stationary tray fermentation
C. both (a) and (b)
D. none of these
Answer» D. none of these
164.

Which type of E.coli strain was chosen to prove the experiment of conjugation?

A. prototrophs
B. auxotrophs
C. polyauxotrophs
D. autotrophs
Answer» D. autotrophs
165.

Pectinase, an enzyme used for increasing yield and for clarifying juice is obtained by

A. A. oryzae
B. A. niger
C. A.flavus
D. all of these
Answer» E.
166.

Mating between species is necessary for recombination to take place.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
167.

Bacitracin, an antibiotic similar to penicillin, is produced by

A. Bacillus polymyxa
B. Streptomyces erythreus
C. Bacillus licheniformis
D. Aspergillus fumigatus
Answer» D. Aspergillus fumigatus
168.

Which of the following microorganism can yield vitamin B12 using methanol as a carbon source?

A. Methanobacterium soehngenii
B. Methanobacillus omelianski
C. Protaminobacter ruber
D. All of the above
Answer» E.
169.

Commercial scale production of amino acids is typically carried out using

A. regulatory mutants to cause overproduction of biochemical intermediates
B. creation of an intentional increase in membrane permeability to increase release of the amino acids
C. both (a) and (b)
D. none of the above
Answer» D. none of the above
170.

Flavor can be enhanced from the

A. L-Alanine
B. D-L-Alanine
C. L-Aspartic acid
D. all of these
Answer» E.
171.

Which of the following was the first amino acid to be produced commercially?

A. L-glutamic acid
B. L-lysine
C. L-cystine
D. L-methionine
Answer» C. L-cystine
172.

It is mandatory that cultures and fermentation residues be sterilized before discard in case of Eremothecium ashbyii and Ashbya gossypii because they are

A. plant pathogens
B. human pathogens
C. plant mutants
D. none of these
Answer» B. human pathogens
173.

What temperature is necessary for the production of vinegar?

A. 43 degree C
B. 60 degree C
C. 10-13 degree C
D. 15-34 degree C
Answer» E.
174.

We require cell-free DNA for transformation to take place.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
175.

The F factor DNA is sufficient to specify how many genes?

A. 2
B. 10
C. 40
D. 100
Answer» D. 100
176.

Which of the following cells of E.coli are referred to as F—?

A. Male cells
B. Female cells
C. Both male and female cells
D. Neither male nor female cells
Answer» C. Both male and female cells
177.

What is the pH required for production of baker’s yeast?

A. 1 to 2
B. 4 to 5
C. 7 to 8
D. 10 to 12
Answer» C. 7 to 8
178.

Which of the following enzymes acts on the DNA after its entry into the cell?

A. ligases
B. endonucleases
C. deoxyribonucleases
D. exonucleases
Answer» D. exonucleases
179.

Penicillium chrysogenum is a better penicillin producing species.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
180.

In which phase of growth does the recipient cell takes up the donor DNA?

A. lag phase
B. early logarithmic phage
C. late logarithmic phage
D. stationary phage
Answer» D. stationary phage
181.

The production of alcohol from lactose of whey is generally carried out by

A. Saccharomyces cerevisiae
B. Candida pseudotropicalis
C. Candida utilis
D. none of these
Answer» C. Candida utilis
182.

The medium for production of Baker’s yeast contains only molasses and inoculum.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
183.

Which of the following yeast can be used to produce microbial protein?

A. Saccharomyces cerevisiae
B. Candida milleri
C. Eremothecium ashbyi
D. Candida utilis
Answer» E.
184.

Gluconic acid is produced by which of the following molds?

A. Aspergillus niger
B. Rhizopus nigricans
C. Aspergillus terreus
D. Rhizopus oryzae
Answer» B. Rhizopus nigricans
185.

Fermentation of rice is carried out by which of the following microorganisms?

A. bacteria
B. yeasts
C. molds
D. protozoa
Answer» D. protozoa
186.

Which of the following enzymes is used to hydrolyze starch to dextrin?

A. invertase
B. pectinase
C. amylase
D. protease
Answer» D. protease
187.

Which of the following techniques is used to improve penicillin production?

A. fed-batch fermentation
B. submerged-culture technique
C. continuous fermentation
D. batch fermentation
Answer» C. continuous fermentation
188.

Which of the following product acts as a substrate for the production of citric acid?

A. molasses
B. corn-steep liquor
C. barn
D. oyabeen meal
Answer» B. corn-steep liquor
189.

Paper, glass beads can be used to immobilize enzymes.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
190.

Which of the following enzyme is used in the process of bating?

A. invertase
B. pectinase
C. amylase
D. protease
Answer» E.
191.

Solvents and enzymes are found in which of the following categories of microbial products?

A. Pharmaceutical chemicals
B. Commercially valuable chemicals
C. Food supplements
D. Alcoholic beverages
Answer» C. Food supplements
192.

Eco R1 cuts the plasmid DNA and the donor DNA such that both the ends are same.

A. True
B. False
C. May be
D. Can't say
Answer» C. May be
193.

Which of the following enzymes cut the DNA molecule at particular nucleotide sequence?

A. restriction endonuclease
B. exonuclease
C. ligase
D. polymerase
Answer» B. exonuclease
194.

Industrial fermentation are performed in large tanks of capacity ______________

A. 100 gal
B. 1000 gal
C. 50,000 gal
D. 10,000 gal
Answer» D. 10,000 gal
195.

Which of the following is not a desired characteristic of the organism to be used for industrial application?

A. should produce less amount of product
B. should be readily available
C. should grow rapidly
D. should be nonpathogenic
Answer» B. should be readily available