introns and exons
What introns and exons means in Biology A-Level, as defined for AQA.
Definitions of introns and exons
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Reference: AQA
Non-coding sequences within genes are called introns, and they separate the coding sequences called exons.
Coding sequences called exons are interrupted by non-coding sequences called introns.
Genes are split into exons, which are coding, and introns, which are not.
Topics that use introns and exons
- DNA and protein synthesis (AQA A-Level)
- DNA, genes and chromosomes (AQA A-Level)
- Using genome projects (A-level only) (AQA A-Level)
Related terms
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