1. Biology pgs. 267-269 Chapter 12 Section 2 Chromosomes and DNA Replication

2. Objectives ____________________the events of DNA replication _____________the DNA molecule to chromosome structure Summarize Relate

3. In prokaryotic cells, DNA is located in the____________________. Most prokaryotes have a single DNA molecule containing nearly all of the cell’s genetic information. cytoplasm

4. Chromosome Structure Eukaryotic chromosomes contain DNA and protein, tightly packed together to form_________________. Chromatin consists of DNA tightly coiled around proteins called______________. chromatin histones

5. Copyright Pearson Prentice Hall DNA and Chromosomes Eukaryotic Chromosome Structure Chromosome Supercoils Nucleosome DNA double helix Histones Coils

6. DNA Replication Each strand of the DNA double helix has all the information needed to reconstruct the other half by the mechanism of_______________ base pairing.

7. The sites where separation and replication occur are called replication forks. Before a cell divides, it duplicates its DNA in a process called____________________. Replication ensures that each resulting cell will have a complete set of DNA. replication

8. During DNA replication, the DNA molecule separates into two strands, then produces two new complementary strands following the rules of base pairing. Each strand of the double helix of DNA serves as a ____________________for the new strand. template

9. Copyright Pearson Prentice Hall DNA Replication Nitrogen Bases Replication Fork DNA Polymerase Replication Fork Original strand New Strand Growth

10. How Replication Occurs DNA replication is carried out by enzymes that _____________a molecule of DNA. Hydrogen bonds between base pairs are broken and the two strands of DNA____________ “unzip” unwind.

11. The principal enzyme involved in DNA replication is DNA polymerase. DNA polymerase joins individual nucleotides to produce a DNA molecule and then “proofreads” each new DNA strand.