Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

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

PCR or polymerase chain reaction was discovered by

  1. Jeffreys

  2. Nakamura

  3. Karry Mullis

  4. Lander

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Kary Mullis. Kary Banks Mullis (born December 28, 1944) is a Nobel Prize-winning American biochemist. In recognition of his invention of the polymerase chain reaction (PCR) technique, he shared the 1993 Nobel Prize in Chemistry with Michael Smith and earned the Japan Prize in the same year.

So, the correct answer is 'Karry Mullis.'

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

The function of polymerase chain reaction (PCR) is

  1. Translation

  2. Transcription

  3. DNA amplification

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Translation is the process of synthesis of protein using mRNA nucleotide sequence as template, it occurs in cytoplasm. Transcription is the process of mRNA synthesis using DNA coding strand as template, it occurs in nucleus. PCR is a technique to amplify the gene of interest in three steps namely denaturation of target DNA (thermal cycle to separate the DNA strands), annealing of primers to the ssDNA and polymerisation (extension of primer into complete DNA strand complementary to the template strand). After completion of one cycle of PCR, two copies of the target DNA are produced both of which serve as template for next PCR cycle and produce 4 copies. Hence, there is exponential amplification of DNA copies. Correct option is C.

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 is useful in

  1. Locating simple sequence repeats

  2. Locating variable number of tandem repeats

  3. Developing restriction maps

  4. Amplification of specific DNA segment.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Polymerase chain reaction (PCR) is a method widely used in molecular biology to make many copies of a specific DNA segment. Using PCR, a single copy (or more) of a DNA sequence is exponentially amplified to generate thousands to millions of more copies of that particular DNA segment.

So, the correct answer is 'Amplification of specific DNA segment.'

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

DNA taq polymerase enzyme is isolated from which bacteria?

  1. Agrobacterium

  2. Thermus aquaticus

  3. Bacillus thuringiensis

  4. E.coli
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

DNA polymerase enzyme was isolated from a thermophilc bacteria called Thermus aquaticus. This is an enzyme used frequently to make multiple copies of segment of DNA by a technique called 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

The whole cycle of gene amplification requires

  1. 15 minutes

  2. 30 minutes

  3. 3 hours

  4. 24 hours.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The denaturation stage of PCR takes about 1–2 minutes. The thermocycler then lowers the temperature to about 50° to 60°C, which allows the short, oligonucleotide primers to anneal to their complementary sequences on the single-stranded DNA molecules. The annealing stage of PCR lasts about 30 seconds. Hence, the whole cycle of gene amplification requires 30 minutes.

So, the correct answer is '30 minutes.'

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

Enzyme required for polymerase chain reaction (PCR) is

  1. RNA polymerase

  2. Ribonuclease

  3. Taq polymerase

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

PCR requires a thermostable DNA polymerase to synthesize new DNA strands during the extension phase. Taq polymerase, isolated from Thermus aquaticus, is the standard enzyme used because it withstands high temperatures.

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

Thermal cycle is used in

  1. Radioactivation

  2. Chemical reaction

  3. Polymerase chain reaction

  4. Enzyme catalysed reactions
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A thermal cycler is an instrument used to perform PCR by precisely controlling the temperature changes required for denaturation, annealing, and extension.

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 methods of which DNA cannot be transferred to the host cell is by

  1. Microinjection

  2. Gene gun

  3. Disarmed pathogen vectors

  4. Polymerase chain reaction
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

PCR is a technique for amplifying DNA in vitro. It is not a method for transferring DNA into a host cell; methods like microinjection, gene guns, and vectors are used for transformation.

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

  1. Is a method of synthesising human protein from human DNA

  2. Uses restriction enzymes

  3. Can produce billions of copies of a DNA fragment

  4. Takes place naturally in bacteria
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

PCR is specifically designed to amplify a specific DNA sequence, producing billions of copies from a small starting amount of template DNA.

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

During PCR technique the pairing of primers to ssDNA segment is called

  1. Denaturation

  2. Annealing

  3. Polymerisation

  4. Isolation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
PCR - technique amplify the DNA sample in three steps namely denaturation of target DNA, annealing and polymerization. Denaturation refers to the thermal cycle that separates the DNA strands and forms the ssDNA. Annealing refers to the pairing of primers to the ssDNA and polymerisation is the extension of primer into complete DNA strand complementary to the template strand. 
So, the correct answer is 'Annealing'