Question

Recognition sequence of restriction enzymes are generally ______________ nucleotides long.

• A. \( 2 \text{ to } 4 \)
• B. \( 4 \text{ to } 8 \)
• C. \( 8 \text{ to } 10 \)
• D. \( 14 \text{ to } 18 \)

Hint:

The length of the recognition site determines how frequently the enzyme will cut a given DNA sequence. A shorter sequence (e.g., 4 bp) will occur more frequently by chance than a longer sequence (e.g., 8 bp).

Answer 1

The Correct Option is B

Restriction enzymes, or restriction endonucleases, are proteins that cut DNA at specific recognition sites. These recognition sequences are typically palindromic (reading the same forwards and backward on opposite strands). The length of these sites is a key characteristic of the enzyme. Most commonly used restriction enzymes recognize sequences that are 4, 6, or 8 base pairs (nucleotides) long. Therefore, the range of 4 to 8 is the correct answer.