Read the Passage carefully and answer the questions.
The DNA fragments can be separated by a technique known as gel electrophoresis. Since DNA fragments are negatively charged molecules, they can be separated by forcing them to move towards the anode under an electric field through a medium/matrix. The separated DNA fragments can be visualised only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation. The repeated amplification of DNA is achieved by the use of a thermostable DNA polymerase (isolated from a bacterium, Thermus aquaticus). After completion of the biosynthetic stage, the product has to be subjected through a series of processes before it is ready for marketing as a finished product. The downstream processing and quality control testing vary from product to product. The convention for naming restriction enzymes is the first letter of the name comes from the genus and the second two letters come from the species of the prokaryotic cell from which they were isolated.
The thermostable DNA polymerase is isolated from -
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Thermus aquaticus
PCR repeats cycles at a high temperature, so it needs a DNA polymerase that is not destroyed by heat. This thermostable DNA polymerase (Taq polymerase) is isolated from the bacterium Thermus aquaticus, which lives in hot springs. The other three options are misspelt forms of the same name.
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Note 2: A similar question was also asked in CUET (UG) 2026 on 06-06-2026 (Slot 1), in CUET (UG) 2025 on 29-05-2025 (Slot 1) and on 16-05-2025 (Slot 1), in CUET (UG) 2024 on 29-05-2024 (Slot 1), and in CUET (UG) 2023 on 30-05-2023 (Slot 1).