✓ Board-verified
Biology · 2023 · 2 marks
Biotechnology : Principles and ProcessesProcesses of Recombinant DNA Technology2 marksUnderstandvery short answer
CBSE 2023 · Region 3 · Set 1 · Q21
(a) 'Insertional inactivation' is a method to detect recombinant DNA. Explain the method.
(a)
'Insertional inactivation' is a method to detect recombinant DNA. Explain the method.
OR
(b)
Explain how recombinant DNA technology is used to detect a disease even before any clinical symptom appears.
Marking-scheme solution
Recombinant DNA/Desired DNA is inserted into the coding sequence of
an enzyme \(\displaystyle \beta\)-galactosidase, this results into inactivation of the gene for the synthesis of this enzymes, presence of chromogenic substrate gives blue coloured colonies if the plasmid in bacteria does not have the insert (Non recombinants), but presence of insert (Recombinants) leads to the growth of bacterial colonies with no colour.
A single stranded DNA or RNA tagged with a radioactive molecule (probe), is allowed to hybridize with its complementary DNA in a clone of cells, followed by detection using autoradiography, the clone having the mutated gene will hence not appear on the photographic film.
//
Polymerase Chain Reaction/PCR is used to detect a disease even before any clinical symptoms appears, involves denaturation, annealing, to amplify DNA of the pathogen using pathogen specific primers
All Biotechnology : Principles and Processes questions2023 question paperNCERT solutions: Biotechnology : Principles and ProcessesPractice Biotechnology : Principles and Processes →
More from Biotechnology : Principles and Processes
- Given below is the restriction site of a restriction endonuclease Pst-I and the cleavage sites on a DNA molecule. 5^′ C-T-G-C-A ↓- G 3^′; 3^′ G ↑-…2023 · asked 2×
- The linking of the antibiotic resistance gene with the plasmid vector of Salmonella typhimurium by Stanley Cohen and Herbert Boyer was made possible…2024
- Which of the following is not required for PCR?2024
- With reference to the set-ups (A, B and C) given below, of the electrophoretic separation of a mixture of DNA fragments of varied lengths, answer the…2024
- (i) Given below is the schematic representation of the process of electrophoresis. Identify the alphabets representing the: (I) Anode end, and (II)…2026
- Assertion: The stirrer facilitates the even mixing of oxygen availability in a bioreactor. Reason (R): Stirred-tank bioreactors generally have a flat…2024
- The organism used in construction of the first artificial recombinant DNA by Cohen and Boyer in 1972 was:2023
- How is DNA isolated in purified form from a bacterial cell? OR Explain how human functional insulin was produced by using recombinant DNA (rDNA)…2025
CBSE Class 12 Biology past-paper question from the 2023 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.