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Which of the following statements is/are correct regarding PCR (Polymerase Chain Reaction)? 1. In this reaction, multiple copies of the gene (or DNA) of interest is synthesized in vitro using two sets of primers (small chemically synthesized oligonucleotides that are complementary to the regions of DNA) and the enzyme DNA polymerase. 2. Real-time RT–PCR is a nuclear-derived method for detecting the presence of specific genetic material in any pathogen, including a virus (COVID-19).  Select the correct answer using the code given below.

Which of the following statements is/are correct regarding PCR (Polymerase Chain Reaction)? 1. In this reaction, multiple copies of the gene (or DNA) of interest is synthesized in vitro using two sets of primers (small chemically synthesized oligonucleotides that are complementary to the regions of DNA) and the enzyme DNA polymerase. 2. Real-time RT–PCR is a nuclear-derived method for detecting the presence of specific genetic material in any pathogen, including a virus (COVID-19).  Select the correct answer using the code given below. Correct Answer Both 1 and 2

The correct answer is Both 1 and 2.

Key Points

PCR (Polymerase Chain Reaction)

  • In this reaction, multiple copies of the gene (or DNA) of interest is synthesized in vitro using two sets of primers (small chemically synthesized oligonucleotides that are complementary to the regions of DNA) and the enzyme DNA polymerase. Hence, Statement 1 is correct.
  • The enzyme extends the primers using the nucleotides provided in the reaction and the genomic DNA as a template.
  • If the process of replication of DNA is repeated many times, the segment of DNA can be amplified approximately a billion times, i.e. 1 billion copies are made. 

RT-PCR (Real-time Polymerase Chain Reaction)

  • Reverse transcription PCR, or RT-PCR, allows the use of RNA as a template. An additional step allows the detection and amplification of RNA.
  • The RNA is reverse transcribed into complementary DNA (cDNA), using reverse transcriptase.
  • The standard PCR procedure is used to amplify the cDNA. The possibility to revert RNA into cDNA by RT-PCR has many advantages.
  • RNA is single-stranded and very unstable, which makes it difficult to work with.
  • Most commonly, it serves as the first step in qPCR, which quantifies RNA transcripts in a biological sample.
  • Real-time RT–PCR is a nuclear-derived method for detecting the presence of specific genetic material in any pathogen, including a virus (COVID-19). Hence, Statement 2 is correct.

Related Questions

The process by which multiple copies of the gene of interest is synthesised in vitro using two sets of primers, is known as
Consider the following statements regarding DNA replication and choose the correct answer:
1. The very first requirement of DNA synthesis is the presence of a template or plan along which the new strand is to be constructed
2. The second requirement is of a DNA-dependent-DNA polymerase or simply DNA polymerase enzyme
3. A DNA Pol cannot join two free nucleotides; one of them must be anchored by hydrogen bonds to a DNA strand
4. Replication takes place bidirectionally
Consider the following two tables and four queries in SQL. Book (isbn, bname), Stock (isbn, copies) Query 1: SELECT B.isbn, S.copies FROM Book B INNER JOIN Stock S ON B.isbn = S.isbn;   Query 2: SELECT B.isbn, S.copies FROM Book B LEFT OUTER JOIN Stock S ON B.isbn = S.isbn; Query 3: SELECT B.isbn, S.copies FROM Book B RIGHT OUTER JOIN Stock S ON B.isbn = S.isbn;   Query 4: SELECT B.isbn, S.copies FROM Book B FULL OUTER JOIN Stock S ON B.isbn = S.isbn;   Which one of the queries above is certain to have an output that is a superset of the outputs of the other three queries?
Choose the appropriate pair of primers to amplify the following DNA fragment by the polymerase chain reaction (PCR).
5'-GACCTGTGG . . . . . . . . ATACGGGAT-3'
3'-CTGGACACC . . . . . . . . TATGCCCTA-5'
Primers
P. 5'-GACCTGTGG-3'
Q. 5'-CCACAGGTC-3'
R. 5'-TAGGGCATA-3'
S. 5'-ATCCCGTAT-3'
Read the passage carefully and choose the best answer to each question out of the four alternatives. Genetic variation is the cornerstone of evolution, without which there can be no natural selection, and so a low genetic diversity decreases the ability of a species to survive and reproduce, explains lead author Yoshan Moodley, Professor at the Department of Zoology, University of Venda in South Africa. Two centuries ago, the black rhinoceros – which roamed much of sub Saharan Africa – had 64 different genetic lineages; but today only 20 of these lineages remain, says the paper. The species is now restricted to five countries, South Africa, Namibia, Kenya, Zimbabwe and Tanzania. Genetically unique populations that once existed in Nigeria, Cameroon, Chad, Eritrea, Ethiopia, Somalia, Mozambique, Malawi and Angola have disappeared. The origins of the 'genetic erosion' coincided with colonial rule in Africa and the popularity of big game hunting. From the second half of the 20th century, however, poaching for horns has dramatically depleted their population and genetic diversity, especially in Kenya and Tanzania.
Sub Sharan Africa has lost how many black rhino genetic lineages in 200 years?
Read the passage carefully and choose the best answer to each question out of the four alternatives. Genetic variation is the cornerstone of evolution, without which there can be no natural selection, and so a low genetic diversity decreases the ability of a species to survive and reproduce, explains lead author Yoshan Moodley, Professor at the Department of Zoology, University of Venda in South Africa. Two centuries ago, the black rhinoceros – which roamed much of sub Saharan Africa – had 64 different genetic lineages; but today only 20 of these lineages remain, says the paper. The species is now restricted to five countries, South Africa, Namibia, Kenya, Zimbabwe and Tanzania. Genetically unique populations that once existed in Nigeria, Cameroon, Chad, Eritrea, Ethiopia, Somalia, Mozambique, Malawi and Angola have disappeared. The origins of the 'genetic erosion' coincided with colonial rule in Africa and the popularity of big game hunting. From the second half of the 20th century, however, poaching for horns has dramatically depleted their population and genetic diversity, especially in Kenya and Tanzania.
Genetic diversity is proportional to _____________________.
Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance with commonly known facts, decide which of the given conclusions logically follow(s) from the statements. Statements: Some cards are postcards. Some cards are envelopes. All envelopes are copies. Conclusions: I. Some copies are envelopes. II. Some postcards are copies. III. Some cards are copies.
Statements : Some clips are copies. Some copies are magazines. No magazines is a dictionary

Conclusions :
I. No copies are dictionary.
II. Some copies are dictionary.
III. Some copies are not dictionary.
IV. No clips are magazines.
In the question below, are given a statement followed by three courses of actions numbered I, II and III. On the basis of the information given, you have to assume everything in the statement to be true, and then decide which of the suggested courses of action logically follow(s) for pursuing. Statement: Soon you would not need to carry original copies of all vehicle papers like driving licence, vehicle registration certificate, insurance, pollution certificate or the permits issued to commercial vehicles with you. According to a ToI report, the Centre plans to amend Motor Vehicles Rules to make it legal for any citizen to carry digital vehicle documents and simultaneously making it compulsory for traffic police to accept digital version of documents. This means that you would not have to carry physical papers in your vehicle as digital copies of the certificates would be valid.  Courses of action: I. The ministry has proposed installation of FASTags on the front windscreens. FASTag is a device that uses radio frequency identification (RFID) technology for making toll payments directly from the user account.  II. To avail the facility, one has to store all the vehicle documents on the government's cloud-based service DigiLocker and when asked he/she can simply display the stored certificates on a smartphone or any other digital devices. These digital copies can be shared with other departments as identity and address proof.  III. The government has increased the maximum load carrying capacity of heavy vehicles, including trucks, by 20-25 per cent besides scrapping the mandatory annual renewal of fitness certificates for freight carriers. Fitness certificates for trucks would now be renewed in every two years not annually.  Which of the following course/courses of action can be said to be said to be a rudimentary course/courses of action?
Which of the following statements(s) concerning natural regions of the world is/are correct? 1) Equatorial climatic regions have less urbanization 2) Mediterranean climatic regions have a high level of urbanization 3) Equatorial climatic regions have a high concentration of human population 4) Mediterranean climatic regions practice plantation farming Select the correct answer using the code given below: