Chapter 24, Problem 100A

Interpretation Introduction

Interpretation : The sequence of DNA before the protein-making machinery of the cell is to be explained.

Concept Introduction : All of the genetic information is contained in DNA, which is the genetic material. DNA's little gene segments make up genes.

Answer to Problem 100A

DNA strands must unwind inside the helix before the protein-making machinery of the cell can “read” the code words formed by the DNA bases.

Explanation of Solution

Each DNA strand is made up of a polynucleotide chain (phosphate groups, sugar units, and nitrogen bases), and when two of these strands are bundled together into a spiral pattern, they form a double helix.

The most stable configuration in a DNA helix is created by hydrogen bonding between the opposing nitrogen bases (adenine and thymine, and guanine and cytosine), which are inside of a double helix and hold it together by joining two polynucleotide chains.

A gene is a piece of DNA that provides instructions for creating a single peptide chain or protein. Three nitrogen bases in the DNA are needed to specify each amino acid in a single peptide chain, and this is how genes work.

The DNA double helix must be unzipped—the helix must unwind to expose a sequence of nitrogen bases—in order for the cell machinery that synthesizes proteins to be able to "read" the code words comprising the DNA bases.

The nitrogen base pairs are situated inside the DNA double helix, and the DNA helix must unwind into two DNA strands in order for the cell machinery that produces proteins to "read" the code words containing the DNA bases.