Tag: pcr

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

A doctor while operating on an HIV(+)ve patient accidentally cuts himself with a scalpel. Suspecting himself to have contracted the virus which test will he take to rule out/confirm his suspicion?

  1. PCR

  2. Routine urine examination

  3. TLC

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

Very low count of bacteria or viruses (when the symptoms of the disease are not yet visible) can be detected by multiplication of their nucleic acid by PCR, (PCR can detect very low amounts of DNA). PCR is usually used to detect HIV in suspected AIDS patients.

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

Given figures represent the steps involved in polymerase chain reaction (PCR). Identify the steps A, B, C and D, and select the correct option.

A B C D
a Denaturation at 94-96 degree C Extension through Taq polymerase at 72 degree C Repetition of denaturation and annealing Annealing at 72 degree C
b Denaturation at 94-96 degree C Annealing at 40-60 degree C Extension through Taq polymerase at 72 degree C Repetition of denaturation and annealing
c Denaturation at 40-60 degree C Annealing at 72 degree C Extension through Taq polymerase at 94-96  degree C Repetition of denaturation and annealing
d Extension through Taq polymerase at 72 degree C Denaturation at 40 degree C Annealing at 72 degree C Repetition of denaturation and annealing

  1. a

  2. b

  3. c

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

Polymerase chain reaction involves the steps:

  • Denaturation
  • Annealing 
  • Extension
  • Amplification
So, the correct option is 'Option B ' .

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

Study the following statements regarding recombinant DNA technology and select the incorrect ones

(i) Taq polymerase extends the primers using the nucleotides provided in the reaction
(ii) Antibiotic resistance genes are considered as desirable genes in recombinant DNA technology
(iii) DNA fragments are separated according to their charge only, in agarose gel electrophoresis
(iv) Transformation is a procedure through which a piece of DNA is integrated into the genome of a host bacterium
(v) To produce higher yields of the desired protein, host cells can be multiplied in a continuous culture
(vi) Downstream processing is one of the steps of polymerase chain reaction

  1. (i), (iii) and (vi)

  2. (i), (iii) and (v)

  3. (ii), (iii) and (v)

  4. (i), (iv) and (v)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Antibiotic resistance genes are selectable markers. Desirable genes are the ones which are introduced in the vector for getting desired protein product. In agarose gel electrophoresis, DNA fragments are separated according to their charge and size. After the formation of the product in a bioreactors, it undergoes through some processes before a finished product is ready for marketing. The processes include separation and purification of products which are collectively called as downstream processing.

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

Reaction of 1989 was

  1. Nicking by restriction endonucleases

  2. Polymerase chain reaction

  3. Reverse genetics

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

In 1985 Norm Arnheim, also a member of the development team concluded his sabbatical at Cetus and assumed an academic position at USC. He began to investigate the use of PCR to amplify samples containing just a single copy of the target sequence. By 1989 his lab developed multiplex-PCR on single sperm to directly analyze the products of meiotic recombination.

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

X technique is now routinely used to detect HIV in suspected AIDs patients. It is being used to detect mutations in genes in suspected cancer patients too. It is a powerful technique to identify many other genetic disorders. Identify X-

  1. X=PCR

  2. X=DNA fingerprinting

  3. X-Bioinformatic

  4. X-X-ray defreaction
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The development of molecular techniques that access viral load and the development of genotypic resistance have revolutionized the treatment of HIV disease. Commercially available viral load assays use a number of different approaches from reverse transcriptase PCR to amplification of branched chain DNA. New real-time PCR assays are under development, including LightCycler- and TaqMan-based tests. So, the correct answer is option A. ( X=PCR ).

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.'