Read the following paragraph carefully and answer the given questions.

In the year 1963 the two enzymes responsible for restricting the growth of bacteriophage in E. coli were isolated. The first restriction endonuclease - Hind II, whose functioning depended on a specific DNA nucleotide sequence was characterized five years later. It was found that Hind II always cut DNA molecules at a particular point by recognizing a specific sequence of six base pairs. This specific base sequence is known as the recognition sequence for Hind II. Besides Hind II, today we know more than 900 restriction enzymes that have been isolated from over 230 strains of bacteria, each of which recognize different recognition sequences.

Restriction enzymes are also known as

Molecular scissors

The correct answer is Option (2) → Molecular scissors      

The cutting of DNA at specific locations became possible with the discovery of the so-called ‘molecular scissors’– restriction enzymes. Restriction enzymes belong to a larger class of enzymes called nucleases. These are of two kinds :exonuclease and endonuclease . Exonuclease remove nucleotides from t