Exam 3 (mean 76%)

Exam 3 (mean 76%)

A 70-63

B 62-56

C 55-49

D 48-42

F 41-0

• Today-Ch 13

• Announcements – Look for Chapter 12 and 13 quizzes

posted this weekend.– Exam 4 covers Chapters 12, 13 and 16 (last

exam you can drop. Everyone must take the final exam)

Biology 190Chapter 16 pictures

DNA Replication occurs at the “S” stage of mitosis

Fig 5.26 Nucleotides

U

ACCCCAG

Fig 16.5 One DNA strand.

Fig 16.6 Double HelixACCCCAG

-T-G-G-G-G-T-C

Chargaff’s Rule

Question 16.1

Functions of Proteins

• Structural• Catalytic activity• Immunity• Regulation • Poisons• Transport molecules• Hormones• Fluid and electrolyte balance • Sources of energy

Fredrick Griffith’s Experiments

Polysaccharide Coat

Fredrick Griffith’s Results

Live R-strainpicked up DNA from the S-strain. Contains genes for “smooth coat”.

Alfred Hershey and Martha Chase

How viruses (phages) infect bacteria

Fig 16.4 Hershey and Chase

Watson and Crick

Rosalind Franklin’s Data(Maurice Wilkins’ Lab)

What exactly IS the structure of DNA?

Chargaff’s Rule

Nucleotide base pairing

Fig 16.7 Structure of DNA

Nobel Prize- 1962Wilkins Crick Watson

Figure 16.9 Semiconservative Model for DNA Replication

Parental strands(template strands)

Daughter strands

DNA Origin of Replication

Bacteria have one origin of replication.

Fig 16.12 Eukaryotic organisms have multipleorigins of replication.

Unwinding DNA

Single-strandedBinding Proteins

Nucleoside Triphosphate

Fig 16.13 DNA Polymerase(Daughter strand) (Parent strand)

(Old strand)

P

Questions 6.3 & 6.4

Fig 16.14ReplicationFork

Leading Strand

5’

3’

Lagging Strand

5’

3’

5’

5’

5’

5’

3’

3’

3’

3’

5’

5’

3’

3’

Old strandsParent strandsTemplate strands

Fig 16.14

DNA Ligase

DNA Polymerase III

Fig 16.13 DNA polymerase needs a 3’ -OH group

Fig 16.16

Fig 16.16. Review of Bacterial DNA Replication

Helicase

SS bindingproteins

Fig 16.18DNA shortening and telomeres

Mismatch repair

2 Purines = bulge

2 Pyrimidines = dimpleT C

G A

Fig 16.17 Excision Repair

Xeroderma Pigmentosa

In very, very, vary rare cases mutations have a

selective advantage