Non-Coding Genes
Biology: AQA A Level, topic 4.1.3
Non-Coding Genes
A large proportion of the genes in eukaryotic DNA do NOT code for any polypeptides. These genes have no biological function and are referred to as non-coding genes.
Exons
- The coding regions in a gene are called exons.
- Sequences of coding genes are interrupted at regular intervals by non-coding regions.
Introns
- The non-coding regions in a gene are called introns.
- When a gene is translated for protein synthesis, the introns are removed from the sequence.
Multiple repeats
- There are also regions of non-coding multiple repeats in eukaryotic DNA.
- Multiple repeats are random sequences in the DNA that will be repeated many times (e.g. CGCCGCCGCCGC).
Test yourself on Non-Coding Genes
Which of the following statements about non-coding genes are true?
What is the name given to coding genes?