Gene Expression (DP IB Biology: HL): Revision Note

Gene expression

• Gene expression is the mechanism by which the genetic code contained within DNA has an effect on the phenotype of an organism

• The most common stages of gene expression include:

  • Transcription -  during which the genetic code is transcribed into mRNA

    • This is an important stage where gene expression may be switched on or off

  • Translation - when the genetic code is translated into proteins at ribosomes

  • The function of the protein product, such as an enzyme, which will affect the phenotype

Transcription, translation and the function of the protein product are the main stages of gene expression in organisms