Which of the following statements given above is/are correct regarding...
To evaluate the correctness of the statements:
- Statement i is correct; Hind II was indeed the first restriction endonuclease characterized and it cuts DNA at a specific six-base pair sequence.
- Statement ii is incorrect; while The convention for naming these 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.
- Statement iii is incorrect; while exonucleases and endonucleases are both nucleases, not all endonucleases are restriction enzymes. Restriction enzymes specifically cut at defined sequences, while exonucleases remove nucleotides from the ends of DNA.
- Statement iv is correct; restriction endonucleases indeed recognize and cut specific palindromic sequences.
Thus, the correct options that reflect true statements are i, ii, and iv, which corresponds to Option C.
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The first restriction endonuclease–Hind II, whose functioning depended on a specific DNA nucleotide sequence was isolated and characterised five years later. It was found that Hind II always cut DNA molecules at a particular point by recognising a specific sequence of six base pairs.
The convention for naming these 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.
Exonucleases remove nucleotides from the ends of the DNA whereas, endonucleases make cuts at specific positions within the DNA
Each restriction endonuclease recognises a specific palindromic nucleotide sequences in the DNA.