Question

Enzymes used in recombinant research are: A. Terminal Transferases B. Pyruvate kinase C. Reverse Transcriptase D. Hexokinase Choose the correct answer from the options given below:

• A. A only \
• B. A and D only \
• C. B and A only \
• D. A and C only

Hint:

Reverse Transcriptase is famous for letting scientists reverse the central dogma, turning RNA into cloneable cDNA. Terminal Transferase is used to create sticky ends for splicing.

Answer 1

The Correct Option is D

Step 1: Concept Recombinant DNA technology (genetic engineering) relies on specialized toolkit enzymes to isolate, copy, alter, and join nucleotide fragments in vitro.

Step 2: Meaning * Genetic engineering tools include enzymes that cut, splice, extend, or copy nucleic acid molecules. * Metabolic enzymes catalyze the chemical reactions that break down nutrients for energy inside regular cellular pathways.

Step 3: Analysis * Terminal Transferase (A) is an enzyme that adds nucleotides to the 3' end of a DNA strand without needing a template, which is highly useful for adding homopolymer tails to cloning vectors $\rightarrow$ Correct. * Pyruvate kinase (B) is a metabolic enzyme that catalyzes the final step of glycolysis, transforming phosphoenolpyruvate into pyruvate to generate ATP. * Reverse Transcriptase (C) is an enzyme that synthesizes complementary DNA (cDNA) from an RNA template, making it essential for cloning expressed genes and constructing cDNA libraries $\rightarrow$ Correct. * Hexokinase (D) is a metabolic enzyme that catalyzes the initial step of glycolysis, phosphorylating glucose inside the cell.

Step 4: Conclusion The primary tools used in recombinant DNA research are A and C, matching option D. Final Answer: (D)