AP EXAM REVIEW SESSION III

MOLECULAR GENETICS

Be prepared, not scared!

Gene Expression

But first . . . A Quick Visit to Mendelian Genetics . . .

1. Paula and Bernie have a child named Liz. Paula is A – and Liz is B +. What are the possible blood phenotypes for Bernie? Genotypes for all?

2. Coat color is Labrador retrievers is controlled by the inheritance and interaction of two genes. Black color is dominant to chocolate, but yellow Labrador retrievers will be produced if a second dominant gene allowing the ability to express pigment is not inherited. Two black Labrador retrievers, heterozygous at both loci, are mated. What is the chance that they will produce yellow offspring?

3. Two carriers for cystic fibrosis have 3 children together, none of whom has cystic fibrosis. What is the probability their 4th child will be born with cystic fibrosis?

4. Two diploid organisms, one heterozygous for 4 genes and one homozygous dominant for 4 genes, sexually reproduce. What is the probability the offspring is heterozygous at every locus?

What is the most likely path of inheritance?

What is the most likely path of inheritance?

What is the most likely path of inheritance?

Nucleic Acids

DNA

DNA

DNA Replication

DNA Replication

Mechanisms of Gene Transfer in Bacteria

Prokaryotic Gene ExpressionInducible vs Repressible Operons

Eukaryotic Protein Synthesis

REGULATION OF EUK GENE EXPRESSION• Pre-Transcriptional Modifications

Chromatin Re-modelingo Acetylation of Histoneso Methylation

Initiation of Transcriptiono Transcription Factors

• Post-Transcriptional Modifications Alternative RNA Splicing mRNA Degradation Protein Processing

Proteosomes

Non-Coding RNAs

REGULATION OF EUK GENE EXPRESSION• Post-Transcriptional

Modifications, cont mRNA Degradation Protein Processing

o Proteosomes Non-Coding RNAs

o microRNAs (miRNAs)o small interfering RNAs (siRNAs)

Techniques in Molecular Genetics

Restriction Enzymes & Recombinant DNA

Gene Cloning

Using mRNA to Produce

cDNA

Microarrays

Polymerase Chain Reaction (PCR)

Electrophoresis

Restriction Fragment Length Polymorphisms, AKA . . . RFLPs

Single Nucleotide PolymorphismsSNPs