Gene Expression and Regulation Overview — AP Biology
1. Unit at a Glance
This unit follows the flow of genetic information described by the central dogma of molecular biology: DNA → RNA → Protein. We start with core nucleic acid structure and how DNA is copied, then walk through each step of gene expression, cover how expression is controlled, what happens when errors occur, and end with modern techniques for manipulating DNA.
Topics build sequentially: understanding DNA structure and replication provides a critical foundation for learning transcription, translation, regulation, and mutations. The AP exam frequently tests connections across these topics, so pay attention to how concepts link together.
Common Pitfalls
Why: These processes share similar-sounding names and base pairing rules, making it easy to mix up key details on the exam.
Why: Silent mutations do not alter amino acids due to genetic code redundancy, and many mutations have neutral or even beneficial effects.
Why: Eukaryotes regulate gene expression at multiple stages from epigenetics through post-translational modification, which the AP exam tests frequently.