Biology

DNA and Genetics

1,095 Questions

DNA and genetics questions explore molecular biology, DNA replication, and genetic engineering techniques. These topics are essential for various competitive exams requiring a strong foundation in life sciences. Practice these questions to understand complex biological processes thoroughly.

DNA replication mechanismsGenetic engineering techniquesGene editing toolsPolymerase chain reactionDNA sequencing methods

DNA and Genetics Questions

Multiple choice

Pallindromes are

  1. base pair sequences which are same when read forward and backward

  2. different base pair sequences when read in forward and backward

  3. made of same base pair

  4. not recognised by restriction endonuclease
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct ans: Pallindronic sequences are those which are same when read from both the sides. e.g. MALAYALAM, 5'GAATTC3' and 3'CTTAAG 5'. 

Multiple choice

The function of DNA LIGASE is

  1. to unwind DNA

  2. to make cuts at specific positions

  3. to form a phosphodiester bond between 5' phosphate group of one nucleotide and 3' hydroxyl group of another nucleotide.

  4. to form a phosphodiester bond between 3' phosphate group of one nucleotide and 5' hydroxyl of other nucleotide.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Correct.

Multiple choice

Alkaline phosphatase has a role in

  1. removing of unwanted nucleotides from the end of DNA

  2. adding of more nucleotides to DNA

  3. the removal of phosphate group

  4. adding of methyl group to one end of DNA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Correct. As the process of ligation requires the presence of 5' phosphate group, Alkaline phosphatase is used to remove phosphate  and prevent unwanted self ligation.

Multiple choice

Molecular glue is another name for

  1. DNA Ligase

  2. restriction enzyme

  3. DNA polymerase

  4. Topoisomerase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct. it is used for joining of two DNA fragments.

Multiple choice

Chemical knives of DNA are

  1. DNA polymerase

  2. Restriction enzyme

  3. RNA synthetase

  4. Reverse transcriptase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Correct. They make cuts at specific position on DNA fragments.

Multiple choice

Which of the following statements regarding the herpes virus is FALSE?

  1. The herpes virus has an 18 hour replication cycle.

  2. Expression of the genome is strictly regulated in herpes virus.

  3. The virus enters the cells through cellular membrane fusion.

  4. The genome is a 120–230 kbp double-stranded, circular DNA.

  5. Viral DNA is synthesised by the help of a large number of viral enzymes.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  The genome of a herpes virus is a 120–230 kbp double-stranded, linear DNA with repeated sequences located at each flank and certain other regions.

Multiple choice

………. is Molecular marker.

  1. RFLP

  2. RLP

  3. RAP

  4. RFP
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Restriction Fragment Length Polymorphism (RFLP) is a classic molecular marker technique used in genetics and biotechnology.

Multiple choice

RFLP stands for:

  1. Restriction Fragment Length Polymorphism

  2. Registered Fragment Length Polymorphism

  3. Restriction Fragment Length Problem

  4. Restriction Fragment Labour Polymorphism
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

RFLP is the standard scientific acronym for Restriction Fragment Length Polymorphism.

Multiple choice

Which of the following statements are FALSE? P. PAM matrices are based on Markov model of protein evolution. Q. SRS is a website that indexes many biological databases and is searchable by keywords. R. Sequences that share an arbitrary, threshold level of similarity determined by alignment of matching bases are termed as homologous sequences. S. The paired dot in the sequence alignment represents semi-conserved substitutions.

  1. Only P and Q

  2. Only P and R

  3. Only P and S

  4. Only Q and R

  5. Only R and S
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It is the correct answer. Both are false. PAM matrices are based on Dayhoff model of protein evolution. The paired dot in the sequence alignment represents conserved substitutions.