Tag: asexual modes of reproduction

Questions Related to asexual modes of reproduction

If the initial number of template DNA molecules in a PCR reaction is $1000$, the number of product DNA molecules at the end of $20$ cycles will be closest to.

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

  1. $10^3$

  2. $10^6$

  3. $10^9$

  4. $10^{12}$

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Correct Option: C

How many cycles of PCR are required if desired number of DNA molecules is 64 and starting material is single stranded DNA instead of ds DNA ?

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

  1. 5

  2. 64

  3. 7

  4. 30

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Correct Option: A

Which does not describe a function of the DNA polymerase molecule?

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

  1. Recognise the free nucleotide that pairs with the base on the template strand of DNA

  2. Read the strand of template DNA and recognise the base there

  3. Proofread to ensure that the proper base has been incorporated

  4. Make the proper nucleotide to match with the base read on the template strand

Show answer
Correct Option: D
Explanation:

DNA polymerase is an enzyme that synthesizes DNA molecules from deoxyribonucleotides, the building blocks of DNA. The function of DNA polymerase is to replicate, proofread and repair DNA.DNA polymerases add nucleotide bases only when an RNA primer, a short piece of RNA, is already present. 

So, the correct option is 'Make the proper nucleotide to match with the base read on the template strand'.

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

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

  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

Show answer
Correct Option: B
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'.

What is the function of the polymerase chain reaction in genetic engineering?

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

  1. Cut DNA into many fragments

  2. Carry DNA into a new cell

  3. Link together newly joined fragments of DNA

  4. Make millions of copies of a specific segment of DNA

Show answer
Correct Option: D
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.

So, the correct option is 'Make millions of copies of a specific segment of DNA'.

In the $PCR$ technology the $DNA$ segment is replicated over a billion times. This repeated replication is catalyzed by the enzyme.

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

  1. $DNA$ polymerase

  2. Taq polymerase

  3. $DNA$ dependent $RNA$ polymerase

  4. Primase

Show answer
Correct Option: B
Explanation:
Taq polymerase is a thermostable DNA polymerase named after the thermophilic bacterium Thermus aquaticus from which it was originally isolated by Chien et al. in 1976. Its name is often abbreviated to Taq Pol or simply Taq. It is frequently used in the polymerase chain reaction (PCR), a method for greatly amplifying the quantity of short segments of DNA.

T. aquaticus is a bacterium that lives in hot springs and hydrothermal vents, and Taq polymerase was identified as an enzyme able to withstand the protein-denaturing conditions (high temperature) required during PCR. Therefore, it replaced the DNA polymerase from E. coli originally used in PCR. Taq's optimum temperature for activity is 75–80 °C, with a half-life of greater than 2 hours at 92.5 °C, 40 minutes at 95 °C and 9 minutes at 97.5 °C, and can replicate a 1000 base pair strand of DNA in less than 10 seconds at 72 °C.

So the correct option is 'Taq polymerase'.

The taq polymerase enzyme is obtained from

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

  1. Thiobacillus ferroxidans

  2. Bacillus subtilis

  3. Pseudomonas putida

  4. Thermus aquaticus

Show answer
Correct Option: D
Explanation:
Taq polymerase is a thermostable DNA polymerase named after the thermophilic bacterium Thermus aquaticus from which it was originally isolated by Chien et al. in 1976. Its name is often abbreviated to Taq Pol or simply Taq. It is frequently used in the polymerase chain reaction (PCR), a method for greatly amplifying the quantity of short segments of DNA.

T. aquaticus is a bacterium that lives in hot springs and hydrothermal vents, and Taq polymerase was identified as an enzyme able to withstand the protein-denaturing conditions (high temperature) required during PCR. Therefore, it replaced the DNA polymerase from E. coli originally used in PCR. Taq's optimum temperature for activity is 75–80 °C, with a half-life of greater than 2 hours at 92.5 °C, 40 minutes at 95 °C and 9 minutes at 97.5 °C, and can replicate a 1000 base pair strand of DNA in less than 10 seconds at 72 °C.

So the correct option is 'Thermus aquaticus'.

Which one is a true statement regarding $DNA$ polymerase used in $PCR$

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

  1. it is used to ligate introduced $DNA$ in recipient cell

  2. it serves as a selectable marker

  3. it is isolated from a virus

  4. it remains active at high temperature

Show answer
Correct Option: D
Explanation:
Taq polymerase is a thermostable DNA polymerase named after the thermophilic bacterium Thermus aquaticus from which it was originally isolated by Chien et al. in 1976. Its name is often abbreviated to Taq Pol or simply Taq. It is frequently used in the polymerase chain reaction (PCR), a method for greatly amplifying the quantity of short segments of DNA.

T. aquaticus is a bacterium that lives in hot springs and hydrothermal vents, and Taq polymerase was identified as an enzyme able to withstand the protein-denaturing conditions (high temperature) required during PCR. Therefore, it replaced the DNA polymerase from E. coli originally used in PCR. Taq's optimum temperature for activity is 75–80 °C, with a half-life of greater than 2 hours at 92.5 °C, 40 minutes at 95 °C and 9 minutes at 97.5 °C, and can replicate a 1000 base pair strand of DNA in less than 10 seconds at 72 °C.

So the correct option is 'it remains active at high temperature'.

Which of the following steps is/are catalysed by Taq polymerase in a PCR?

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

  1. Denaturation of template DNA

  2. Annealing of primers to template DNA

  3. Extension of primer end on template DNA

  4. All of these

Show answer
Correct Option: C
Explanation:

PCR is the short form for polymerase chain reaction which is the phenomenon which is used for amplification of the part-specific region of DNA as per our interest. Taq polymerase is the enzyme that attaches nucleotides together and help is the extension of primer end on the template DNA.

So, the correct answer is 'extension of primer end on the template DNA'.

Which among the following is true for protein synthesis in bacteria?

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

  1. It involves all the three types of RNAs (m-RNA, t-RNA and r-RNA)

  2. It involves $3$ types of RNA polymerase

  3. It involves single type of RNA polymerase

  4. It involves RNA processing

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Correct Option: C