CHAPTER 9DNA: The Genetic Material 189
Quick Review Looking Ahead
Answer the following without referring to
earlier sections of your book.
1.Describethe structure of chromosomes.
(Chapter 6, Section 1)
2.Definethe term gene.(Chapter 6, Section 1)
3.Identifythe stage in a cell cycle in which DNA
is copied.(Chapter 6, Section 2)
4.Identifyhow changes in DNA cause mutations.
(Chapter 6, Section 3)
5.SummarizeMendel’s theory of heredity.
(Chapter 8, Section 2)
Did you have difficulty? For help, review the
sections indicated.
Section 1
Identifying the Genetic Material
Transformation
Viral Genes and DNASection 2
The Structure of DNA
A Winding Staircase
Discovering DNA’s StructureSection 3
The Replication of DNA
The Roles of Enzymes in DNA Replication
The Rate of Replicationhttp://www.scilinks.org
National Science Teachers Association sciLINKS Internet
resources are located throughout this chapter.Reading Activity
Before you read this chapter, write a short list of
all the things you know about DNA. Then write
a list of the things that you want to know about
DNA. Save your list, and to assess what you
have learned, see how many of your own ques-
tions you can answer after reading this chapter.
Each human cell contains about 6 billion pairs of
nucleotides—one pair for each “step” in the winding
staircase of the DNA model shown on the facing page.
DNA: The
Genetic Material
CHAPTER
9
6C