1. GENETIC INFORMATION - 1. OVERVIEW
Storage of Genetic Information
Structure of DNA Ch 9
Making Copies of Genetic Information
Replication of DNA Ch 9 – DNA Ch 11 & 12 - Cells
Using Genetic Information to Make Cell Structures and Regulate Energy Use
Process of Gene Expression Ch 10
An Overview of Information Flow in a Cell
Gene Transcription DNA => RNA
Translation RNA => Protein
Proteins – cell structures & tools (F10.8, p. 175)
Copyright © 2005 Pearson Prentice Hall, Inc.

2. Copyright © 2005 Pearson Prentice Hall, Inc.
transcription
rRNA
+ proteins
mRNA
tRNA
ribosomes
tRNA
amino acids
translation
Figure :10-8
Title:
An overview of information flow in a cell, from gene transcription to chemical reactions catalyzed by enzymes
Caption:
modification
degradation
Copyright © 2005 Pearson Prentice Hall, Inc.

3. Figure: 9-UO
Title:
Inheritance
Caption:
Inheritance provides for both similarity and difference. All dogs share many similarities because their genes are nearly identical. The enormous variety of body size, fur length and color, and proportion among breeds results from tiny differences in their genes.

4. Chapter 9 DNA: The Molecule of Heredity
Copyright © 2005 Pearson Prentice Hall, Inc.

5. Discovery That Genes Are Made of DNA
Transformed Bacteria Revealed the Link Between Genes & DNA
Transformed bacteria (F9.1 p. 150)
Unnumbered Figure 1 Pyrimidine nucleotides (p. 151)
Unnumbered Figure 2 Purine nucleotides (p. 151)
Copyright © 2005 Pearson Prentice Hall, Inc.

6. Bacterial strain(s) injected into mouse Results Conclusions
R strain does
not cause
pneumonia.
Living
R strain
S strain causes
pneumonia.
Living
S strain
Figure :9-1
Title:
Transformed bacteria
Caption:
Griffith's discovery that bacteria can be transformed from harmless to deadly laid the groundwork for the discovery that DNA contains genes. Question If Griffith had used malaria, which is caused by a single-celled eukaryote, instead of pneumonia, would his experiment have had the same result?
Heat-killed S
strain does not
cause pneumonia.
Heat-killed
S strain
A substance from
heat-killed S strain
can transform the
harmless R strain
into a deadly
S strain.
Living R strain,
heat-killed
S strain

7. Structure of DNA DNA: Composed of Four Nucleotides
DNA: Double Helix of Two Nucleotide Polymers
X-ray diffraction of DNA - Rosalind Franklin
(F9.2 p. 152)
Watson-Crick model of DNA structure (F9.3 p. 153)
The discovery of DNA (FE9.1 p. 154)
Copyright © 2005 Pearson Prentice Hall, Inc.

8. phosphate base = adenine sugar phosphate sugar base = guanine
Figure: 9-UN2
Title:
Purine nucleotides
phosphate
sugar
base = guanine

9. Figure :9-2
Title:
X-ray diffraction studies of DNA taken by Rosalind Franklin
Caption:
(a) The X formed of dark spots is characteristic of helical molecules such as DNA. Measurements of various aspects of the pattern indicate the dimensions of the DNA helix; for example, the distance between the dark spots corresponds to the distance between turns of the helix. (b) Rosalind Franklin published about 40 scientific papers before her untimely death in 1958 at the age of 37.

10. Figure: 9-3
Title:
The Watson-Crick model of DNA structure
Caption:
(a) Hydrogen bonding between complementary base pairs holds the two strands of DNA together. Three hydrogen bonds hold guanine to cytosine; two hydrogen bonds hold adenine to thymine. (b) Strands of DNA wind about each other in a double helix, like a twisted ladder, with the sugar-phosphate backbone forming the uprights and the complementary base pairs forming the rungs. (c) A space-filling model of DNA structure. Question Which are harder to break, A-T bonds or C-G bonds?

11. Figure: E9-1
Title:
The discovery of DNA
Caption:
James Watson and Francis Crick with a model of DNA structure.

12. Structure of DNA
Hydrogen Bonds Between Complementary Bases Hold the Two DNA Molecules Together
The Order of Nucleotides in DNA Can Encode Vast Amounts of Information
Copyright © 2005 Pearson Prentice Hall, Inc.

13. DNA Replication: The Process
The Replication of DNA Is a Critical Event in a Cell’s Life
DNA Replication Produces Two DNA Double Helices, Each with One Old Strand and One New Strand
Basic features of DNA replication (F9.4 p. 155)
DNA replication (F3 p. 158)
Copyright © 2005 Pearson Prentice Hall, Inc.

14. free nucleotides Figure :9-4 Title: Basic features of DNA replication
Caption:
During replication, the two strands of the parental DNA double helix separate. Free nucleotides that are complementary to those in each strand are joined to make new daughter strands. Each parental strand and its new daughter strand then form a new double helix.
free nucleotides

15. replication forks DNA helicase DNA helicase DNA polymerase #1 DNA
replication bubble
DNA polymerase #1
continuous
synthesis
discontinuous
synthesis
DNA
polymerase #2
DNA polymerase #1
continues along parental
DNA strand
DNA polymerase #2
leaves
continuous synthesis
Figure: E9-2
Title:
Details of DNA replication
Caption:
(a) DNA helicase separates the parental strands to form a replication bubble. (b) DNA polymerase synthesizes new pieces of DNA. (c) DNA helicase and DNA polymerase move along a replication bubble. (d) DNA ligase joins the small DNA segments into a single daughter strand. Question During synthesis, why doesn't DNA polymerase move away from the replication fork on both strands?
discontinuous synthesis
DNA
polymerase #3
DNA polymerase #3
leaves
DNA
polymerase #4
DNA ligase joins
daughter DNA strands

16. DNA replication
Figure: 9-UN3
Title:
DNA replication

17. DNA Replication: Accuracy
Genetic Constancy During Cell Reproduction
Proofreading: Produces Almost Error-Free Replication of DNA
1 Replication Error/ 1,000 to 10,000 BP
Proofreading => 1 Error/1,000,000 BP
Mistakes Do Happen
Produces Variability
Natural Selection Can Only Act on Variants that Exist
Essential for Evolution
Good for Population, Even if Bad for Individual
Human Vs. HIV
Copyright © 2005 Pearson Prentice Hall, Inc.