[Campbell Biology P.1009] Which of the following statements about antigen receptor gene rearr... | Practice Question

Which of the following statements about antigen receptor gene rearrangement is correct?

  • A: The enzyme RNA polymerase is responsible for linking V and J gene segments.
  • B: Gene rearrangements are temporary and reversed after lymphocyte activation.
  • C: After light-chain and heavy-chain genes are rearranged, the genes are transcribed, and the transcripts are translated into antigen receptors.
  • D: Recombinase randomly links any one of the 5 V gene segments to any one of the 40 J gene segments for the light-chain gene.

Explanation

The text explicitly states: "After both a light-chain and a heavy-chain gene have been rearranged, antigen receptors can be synthesized. The rearranged genes are transcribed, and the transcripts are processed for translation." This sequence of events rearrangement -> transcription -> translation correctly describes the process. Option A is incorrect because recombinase, not RNA polymerase, links V and J segments. Option B is incorrect as rearrangements are permanent. Option D reverses the correct numbers of V and J segments for the light-chain gene.