Explore topic-wise MCQs in Microbiology.

This section includes 17 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.

1.

The components found in all prokaryotic transcription terminators is

A. a poly-U region
B. Rho factor
C. a hairpin structure
D. none of these
Answer» D. none of these
2.

A specific __________ factor helps RNA polymerase bind to late promoters and transcribe late genes.

A. sigma
B. beta
C. delta
D. gamma
Answer» B. beta
3.

Which of the following enzyme(s) is/are required for lactose fermentation?

A. Transacetylase
B. -galactosidase
C. Galactoside permease
D. All of these
Answer» E.
4.

Which of these catalyzes the synthesis of RNA from a DNA template?

A. DNA gyrase
B. DNA ligase
C. DNA polymerase
D. RNA polymerase
Answer» E.
5.

The location of first hexameric sequence typically found in pro-karyotic promoters is

A. at the transcription start site
B. approximately 35 bases upstream of the transcription start site
C. approximately 10 bases upstream of the transcription start site
D. approximately 25 bases upstream of the transcription start site
Answer» C. approximately 10 bases upstream of the transcription start site
6.

The sigma factor

A. is responsible for recognizing the termination sequence
B. provides the catalytic function of cleaving off pyrophosphates during mRNA synthesis
C. recognizes the promotor
D. accomplishes DNA restriction
Answer» D. accomplishes DNA restriction
7.

The synthesis of mRNA based on a DNA template is called

A. DNA replication
B. transcription
C. translation
D. DNA restriction
Answer» C. translation
8.

An mRNA transcript of a gene contains

A. a start codon
B. a stop codon
C. a terminator
D. all of these
Answer» E.
9.

Recognition/binding site of RNA polymerase is called

A. receptor
B. promoter
C. facilitator
D. terminator
Answer» C. facilitator
10.

Which of the following proteins first binds to TATA box during transcription?

A. TF II A
B. TF II D
C. TF II B
D. RNA polymerase
Answer» C. TF II B
11.

Which of the following enzyme is used for synthesis of RNA under the direction of DNA?

A. RNA polymerase
B. DNA ligase
C. DNA polymerase
D. RNA ligase
Answer» B. DNA ligase
12.

What is the usual sequence of a Pribnow box?

A. AUAUA
B. TATAAT
C. UUUUU
D. TTGACA
Answer» C. UUUUU
13.

Which of the following component of RNA polymerase facilitates the recognition of promoter sequences?

A. a subunit
B. b subunit
C. s subunit
D. c subunit
Answer» D. c subunit
14.

Which of the following statement defines a replicon?

A. A DNA molecule that encodes pili for conjugation
B. A DNA molecule that is able to replicate and be maintained
C. A DNA template which is used in transcription
D. The enzyme responsible for transposition
Answer» C. A DNA template which is used in transcription
15.

Which eukaryotic RNA polymerase makes tRNA's?

A. RNA polymerase 1
B. RNA polymerase 2
C. RNA polymerase 3
D. Any of these
Answer» D. Any of these
16.

Which of the following is a product of transcription?

A. mRNA
B. tRNA
C. rRNA
D. all of these
Answer» E.
17.

A level of regulation, demonstrated by the termination of transcription if tryptophan is abundant, by the tryptophan operon in E.coli cells is called

A. activation
B. attenuation
C. corepression
D. desiccation
Answer» C. corepression