Chapter 13, Problem 27A

Summary Introduction

Introduction:

After sequencing the entire human genome, the scientists found that less than two percent of all the nucleotides in the human genome code for all the proteins in the body. Hence, there are long stretches of DNA that have no direct function. These regions are called noncoding sequences.

Answer to Problem 27A

Correct answer :

The correct answer is option C. to identify individuals who have committed crimes

Explanation of Solution

Explanation/justification for the correct answer:

Option C. to identify individuals who have committed crimes− The noncoding regions of DNA are unique to each individual. When these regions are cut by restriction enzymes, the set of DNA fragments produced are unique to each individual. DNA fingerprinting involves separating DNA fragments using gel electrophoresis to observe the banding patterns unique to each person. This technique is used by forensic experts to identify suspects and victims in criminal cases.

Hence, this is the correct option.

Explanation for incorrect answer:

Option A. to sequence DNA from bacteria− Restriction enzymes were used to produce DNA fragments which were then sequenced using automated machines. DNA fingerprinting was not used to sequence DNA from bacteria. Hence, this is not the correct option.

Option B. to separate DNA fragments- Gel electrophoresis is used to separate DNA fragments and not DNA fingerprinting. Hence, this is not the correct option.

Option D. to identify single nucleotide polymorphisms− Variations in specific nucleotides that are linked to human diseases, are called single nucleotide polymorphisms or SNPs. These variations in the DNA sequence occur when a single nucleotide in the genome is altered. HapMap is used to identify single nucleotide polymorphisms and not DNA fingerprinting. Hence, this is not the correct option.