Identify the wrong statement with regard to Restriction Enzymes.
Answer: (C) Each restriction enzyme functions by inspecting the length of a DNA sequence. Answer: (C) Each restriction enzyme functions by inspecting the length of a DNA sequence Solution: Statements (A), (B) and (D) are all correct: restriction enzymes are core tools of genetic engineering, sticky ends generated by them are joined by DNA ligase, and they cut DNA at palindromic sites.
- A.They are useful in genetic engineering
- B.Sticky ends can be joined by using DNA ligases
- C.Each restriction enzyme functions by inspecting the length of a DNA sequence✓
- D.They cut the strand of DNA at palindromic sites
Correct Answer
(C) Each restriction enzyme functions by inspecting the length of a DNA sequence
Solution & Explanation
Answer: (C) Each restriction enzyme functions by inspecting the length of a DNA sequence Solution: Statements (A), (B) and (D) are all correct: restriction enzymes are core tools of genetic engineering, sticky ends generated by them are joined by DNA ligase, and they cut DNA at palindromic sites. Statement (C) is taken as the wrong/intended answer because a restriction endonuclease recognises a specific palindromic base SEQUENCE rather than merely 'inspecting length'. (answer_source: external — NEET 2020 had no printed biology key; this answer is NCERT-derived and matches the accepted key, though note the NCERT prose itself uses the phrase 'inspecting the length', making the item disputable.) NCERT Reference: Ch 9, p.166, line(s) 13-14 — "Each restriction endonuclease recognises a specific palindromic nucleotide sequences in the DNA"