2. Reverse transcriptase enzyme
Transposons
“Jumping genes”
Function
Other proteins
10%
Retrotransposons
RNA Intermediate
DNA
Reverse transcriptase enzyme

3. Regular Satellite DNA –
Repetitive DNA
Nucleotide Sequence
Tandemly repetitive DNA –
10-15%
short
Satellite DNA
Genetic disorders (triplets)
Interspersed repetitive DNA –
25-40%
Long
Scattered
Similar
10-1 million
Alu Elements
Regular Satellite DNA –
10,000-1 million times
Telomeres and centromeres
Minisatellite DNA –
10-10,000 times
Microsatellite DNA –
Fingerprints
1-10 times

4. Gene Amplification Also selective loss of genes Insects
Selective replication
Cancer cells
Example: Developing ovum
More ribosomes
Later broken down
Also selective loss of genes
Insects

5. Collection of similar genes
Multigene Family
Collection of similar genes
Repetitive DNA
Example: hemoglobin
Pseudogenes

6. Immunoglobulin Genes Cell differentiation
identify viruses and bacteria
Many rearragnements
Binds to epitope on antigen

7. 5 Words of Review Enzymes (genes and coding)
Dehydration Synthesis (retrotransposons)
Disulfide Bridges (antibody molecules)
Evolution (multigene families)
Photorespiration (useless like pseudogenes)

8. Review Questions
What are the two types of repetitive DNA and what is the difference between the two?
What is the purpose of gene amplification and one example?
What is a multigene family?
What causes multigene families?

9. Review Questions What is the basic structure of immunoglobulin genes?
What is done to the gene that specifies it as an immunoglobin gene?
How can transposons change the function of different genes?
What is a sequence of DNA that seems to code for a protein but is lacking something that causes that certain gene to be expressed?