Chapter 13, Problem 15A

Summary Introduction

Introduction:

Some bacteria contain proteins called restriction enzymes that recognize and bind to specific DNA sequences and cleave the DNA within that sequence. The ends of DNA fragments created by restriction enzymes may have sticky ends or blunt ends. The sticky ends produce single stranded DNA that is complementary. The blunt ends do not have regions of single stranded DNA.

Answer to Problem 15A

Correct answer :

The correct answer is option B. EcoRV

Explanation of Solution

Explanation/justification for the correct answer:

Option B. EcoRV − This enzyme creates blunt ends as it is cutting straight across both the strands. Blunt ends do not have regions of single stranded DNA and can join to any other DNA fragment with blunt ends. Hence, this is the correct option.

Explanation for incorrect answer:

Option A. EagI − This enzyme creates sticky ends as it is producing single stranded DNA that is complementary. Hence, this is not the correct option.

Option C. NsiI - This enzyme creates sticky ends as it is producing single stranded DNA that is complementary. Hence, this is not the correct option.

Option D. TaqI − This enzyme creates sticky ends as it is producing single stranded DNA that is complementary. Hence, this is not the correct option.