Unit 6: Gene Expression and Regulation

AP Biology — 18 practice questions with detailed explanations. Use the links below to open each full question page (ideal for search indexing and deep study).

Unit summary

This unit covers core ideas tested on the AP exam. Each listed item links to a standalone page with the full stem, answer choices where applicable, a step-by-step explanation, and the correct answer. Difficulty labels help you prioritize review.

Questions in this unit

Sample prompts

Short previews of topics covered (not full question text).

  • During the elongation phase of translation, a charged tRNA enters the A site of …
  • Although nearly all somatic cells in a multicellular eukaryotic organism contain…
  • In the bacterium *E. coli*, the *trp* operon is repressed when tryptophan is abu…
  • A mutation occurs in a gene such that a single nucleotide pair is deleted from t…
  • A scientist uses the polymerase chain reaction (PCR) to amplify a specific segme…
  • During the modification of a eukaryotic pre-mRNA molecule, a 5' cap is added. Wh…
  • A researcher analyzes a nucleic acid sample and determines that it contains urac…
  • Which of the following best explains why DNA replication is considered discontin…
  • Based on the data, which of the following would be the most likely effect of a m…
  • The process of RNA splicing involves the removal of…
  • Which of the following is a consequence of a frameshift mutation?…
  • The use of CRISPR-Cas9 technology for genome editing has revolutionized the fiel…