Explore topic-wise MCQs in Cytogenetics.

This section includes 22 Mcqs, each offering curated multiple-choice questions to sharpen your Cytogenetics knowledge and support exam preparation. Choose a topic below to get started.

1.

DNA replication in the two strands proceed in opposite direction as they are aligned oppositely with respect to 3’ and 5’ ends( 5’——————————-3’ 3’——————————-5’).In this context which of the following is true.

A. The two arms of the DNA Pol are exactly same with same orientation
B. The two arms of the DNA Pol are exactly same with opposite orientation
C. The two arms of the DNA Pol have different catalytic mechanism i.e. one polymerizes 3’ -> 5’ other 5’ -> 3’
D. The two arms are isomers i.e. they have different arrangement of the subunits.
Answer» B. The two arms of the DNA Pol are exactly same with opposite orientation
Discussion
2.

What constitutes Primosome?

A. Dna a, Dna b, Dna c, Dna G
B. Dna b, Dna G
C. Dna c, Dna b
D. Dna a, Dna c
Answer» C. Dna c, Dna b
Discussion
3.

Rolling circle mode of replication is ________

A. Conservative
B. Non Conservative
C. Semi – Conservative
D. Dispersed
Answer» D. Dispersed
Discussion
4.

Which of this subunit is not a part of core DNA polymerase?

A. Alpha
B. Beta
C. Theta
D. Eta
Answer» C. Theta
Discussion
5.

In an experiment you use DNA pol I – Klenow fragment. When all other requisites for replication are added, then what will be the effect on the newly replicated DNA? Consider leading strand only.

A. No difference from intact DNA pol I replication
B. Replication will be slower
C. Replication will be error prone
D. DNA produced will be shorter
Answer» E.
Discussion
6.

How many prokaryotic DNA polymerases have 5’->3’ proofreading activity?

A. 1
B. 2
C. 3
D. 4
Answer» B. 2
Discussion
7.

You grow a bacterial culture in a media containing N15 and transfer it to a media with N14. After two rounds of replication you perform a CsCl density gradient centrifugation of the DNA. How many bands will you observe what will be their intensity?

A. One, very intense
B. Two, equally intense
C. Three with middle one more intense than upper and lower
D. Three equally intense
Answer» C. Three with middle one more intense than upper and lower
Discussion
8.

WHICH_OF_THIS_SUBUNIT_IS_NOT_A_PART_OF_CORE_DNA_POLYMERASE??$

A. Alpha
B. Beta
C. Theta
D. Eta
Answer» C. Theta
Discussion
9.

What constitutes Primosome?$

A. Dna a, Dna b, Dna c, Dna G
B. Dna b, Dna G
C. Dna c, Dna b
D. Dna a, Dna c
Answer» C. Dna c, Dna b
Discussion
10.

Rolling circle mode of replication is ________$

A. Conservative
B. Non Conservative
C. Semi – Conservative
D. Dispersed
Answer» D. Dispersed
Discussion
11.

DNA replication in the two strands proceed in opposite direction as they are aligned oppositely with respect to 3’ and 5’ ends$

A.
B. .
Answer» B. .
Discussion
12.

Acyclovir is a drug used to treat viral infection by impairing its replication. Why will it not effect bacterial replication as well?

A. Bacteria under viral attack don’t replicate
B. Viral polymerase binds to it and thus can’t perform its function
C. Virus uses it in a polymerization
D. Cellular mechanism deactivates it
Answer» D. Cellular mechanism deactivates it
Discussion
13.

If we mutate the DNA ligase and observe the length of the replicated strands in different time slots after replication initiation, what will we observe?

A. The DNA will gradually increase in length till it is fully replicated
B. Small fragments of DNA will be obtained increasing in number with time
C. Mixture of small and long Fragments of definite length from the start whose concentration simply increases with time
D. At first small fragment, then two separate bands showing long fragment with increasing length and short fragments of definite length.
Answer» E.
Discussion
14.

You take a circular ssDNA and to it you attach a small labeled complimentary fragment. You add different reagents and try to get free labeled probe. Which of this reagent will give you your desired result?

A. Dna b
B. Dna c
C. Dna G
D. Dna a
Answer» B. Dna c
Discussion
15.

In an experiment you use DNA pol I – Klenow fragment. When all other requisites for replication are added, then what will be the effect on the newly replicated DNA? Consider leading strand only.$

A. No difference from intact DNA pol I replication
B. Replication will be slower
C. Replication will be error prone
D. DNA produced will be shorter
Answer» E.
Discussion
16.

In an experiment you take a DNA in vitro and attempt to replicate it. Which combination will you add to your DNA to get the maximum replication product?

A. Dna a, Dna b, HU, SSB, topoisomerase I, polymerase I
B. Dna a, Dna b, HU, SSB, polymerase III
C. Dna a, Dna b, Dna c, HU ,SSB polymerase I
D. Dna a, Dna b, Dna c, HU, SSB, polymerase III
Answer» D. Dna a, Dna b, Dna c, HU, SSB, polymerase III
Discussion
17.

Bacterial polymerases are slower than eukaryotic polymerases.

A. True
B. False
Answer» C.
Discussion
18.

Which is the most processive of prokaryotic DNA polymerases?

A. pol I
B. pol II
C. pol III
D. klenow fragment
Answer» D. klenow fragment
Discussion
19.

How many prokaryotic DNA polymerases have 5’->3’ proofreading activity?$

A. 1
B. 2
C. 3
D. 4
Answer» B. 2
Discussion
20.

At which end are the new DNA bases added?

A. 5’ triphosphate end
B. 3’ triphosphate end
C. 5’ OH end
D. 3’ OH end
Answer» E.
Discussion
21.

What will be the fate of a Seq A mutant E. Coli?

A. DNA replication will occur less frequently
B. Replication will be error prone
C. Replication will not occur
D. Uncontrolled replication
Answer» C. Replication will not occur
Discussion
22.

You grow a bacterial culture in a media containing N15 and transfer it to a media with N14. After two rounds of replication you perform a CsCl density gradient centrifugation of the DNA. How many bands will you observe what will be their intensity?

A. One, very intense
B. Two, equally intense
C. Three with middle one more intense than upper and lower
D. Three equally intense
Answer» C. Three with middle one more intense than upper and lower
Discussion