Biology

DNA and Genetics

985 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 bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Which of the following has popularised the PCR(Polymerase chain reactions)?

  1. Easy availability of DNA template

  2. Availability of synthesis primers

  3. Availability of cheap deoxyribonucleotides

  4. Availability of thermostable DNA polymerase
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Polymerase chain reaction (PCR) relies on repeated cycles of heating and cooling for denaturation and annealing, which would normally destroy standard enzymes. The breakthrough that popularized PCR was the discovery of thermostable DNA polymerase, such as Taq polymerase, which can withstand high temperatures without denaturing.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Which of the following technique is employed to check the progression of a restriction enzyme digestion?

  1. PCR

  2. Bioreactor

  3. Gel electrophoresis

  4. Micro injection
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Answer is option C i.e. "Gel electrophoresis"
Gel electrophoresis is the technique which can check DNA fragment progression. Restriction enzyme digest DNA into fragments. Each fragment has different size. When gel electrophoresis is performed each fragment with different sizes are separated on the gel.
While, PCR is used for DNA amplification. Bioreactors are the fermentors used for fermentation process and micro-injection is a method used to transfer genes between animals.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Kary B Mullis got Nobel prize for discovering 

  1. DNA polymerase enzyme

  2. Polymerase chain reaction

  3. Restriction endonucleases

  4. Western blotting
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

DNA polymerase enzyme synthesizes DNA strands by adding deoxyribonucleotides to 3' end of the primer via phosphodiester bonds; it uses parental DNA as a template. Kary Mullis got Nobel prize, in 1993 in chemistry, for the invention of polymerase chain reaction (PCR).  PCR - technique amplify the gene of interest.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

One of the major advantages of transforming bacteria with a plasmid that contains DNA of interest is to amplify the DNA.
What other laboratory technique can be used to achieve the same result?

  1. Polymerase chain reaction

  2. Restriction fragment length polymorphism analysis

  3. DNA hybridization

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

Polymerase chain reaction is a method of amplifying a specific segment of DNA by making multiple copies of it, using primers and DNA polymerase

So, the correct answer is 'Polymerase chain reaction'

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

PCR and RFLP are employed in

  1. DNA sequencing

  2. Genetic engineering

  3. Study of enzymes

  4. Genetic transformation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

PCR and RFLP (Restriction Fragment Length Polymorphism) are fundamental tools used in genetic engineering for DNA analysis, cloning, and mapping.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Polymerase chain reaction employs

  1. Primers and DNA ligase

  2. DNA ligase only

  3. DNA polymerase only

  4. Primers and DNA polymerase
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

PCR requires primers to define the target region and a DNA polymerase to extend the strands. DNA ligase is not used in PCR.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

What is true about DNA polymerase used in PCR?

  1. It is used to ligate introduced DNA in recipient cells.

  2. It serves as selectable marker.

  3. It is isolated from a virus.

  4. It is active at high temperature.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The DNA polymerase used in PCR (like Taq) is derived from thermophilic bacteria, making it heat-stable and capable of remaining active through the repeated high-temperature denaturation cycles.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Amplification of gene of interest by using PCR may go upto

  1. 0.1 million

  2. 1.0 million

  3. 1.0 billion

  4. 1.0 trillion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

PCR is a powerful technique for amplifying DNA sequences. Through repeated cycles of denaturation, annealing, and extension, a single DNA molecule can be amplified to approximately 1 billion copies.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Taq polymerase is isolated from which bacteria?

  1. E. coli

  2. Bacillus thuringiensis

  3. Thermus aquaticus

  4. Agrobacterium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Taq polymerase is named after the bacterium Thermus aquaticus, which lives in hot springs and provides a heat-stable enzyme necessary for PCR.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

Polymerase chain reaction (PCR) is used for

  1. In vivo replication of specific DNA sequence using thermostable DNA polymerase

  2. In vitro synthesis of mRNAIn vivo synthesis of mRNA

  3. In vitro replication of specific DNA sequence using thermostable DNA polymerase

  4. Separation of DNA fragments according to their size
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

PCR is an in vitro technique used to amplify specific DNA sequences. It utilizes a thermostable DNA polymerase to synthesize multiple copies of the target DNA.

Multiple choice bio-chemistry applications of biotechnology pcr cutting, insertion and ligation of dna gene cloning procedure biotechnological regulations asexual modes of reproduction

To carry out a polymerase chain reaction (PCR), one must have the catalytic DNA polymerase and

  1. a blueprint or gene map of the sequence one wish to copy

  2. a number of primers from either side of the target DNA in order to get the polymerase replication process- going

  3. a DNA synthesizer machine

  4. a DNA probe
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Polymerase Chain Reaction is a method widely used to make many copies of a specific DNA segment. Using PCR, a single (or more) copy of a DNA sequence is exponentially amplified to generate thousands to millions of more copies of that particular DNA segment. Components of PCR include DNA template, DNA polymerase, two DNA primers, nucleotides.

So, the correct option is 'a number of primers from either side of the target DNA in order to get the polymerase replication process-ongoing'.