Alternative Splicing, Translation, and Regulation

Polypeptides/proteins are synthesized based on mRNA sequence.
- Bases and codons define peptide sequence via the genetic code.
- tRNA anticodons are complementary and act as amino acid carriers.
The genetic code has redundancy.
Start and stop codons are important for translation.
Translation steps: initiation, elongation, and termination.
Determine polypeptide sequence from mRNA or DNA sequence.
Ribosomes are agents of protein synthesis.

The lac operon regulates expression of lactose-digesting proteins.
- The repressor and operator regulate translation; lactose interacts with the repressor.
- The operon is a cluster of regulatory and protein-coding genes.
Predict outcomes of defective operators or repressors in the lac operon.
X-inactivation is a regulatory process; necessary in some animals.
- X-inactivation results from chromosome condensation.
- Barr body definition.