Protein synthesis - Higher
Protein synthesis consists of two stages – transcription and translation. In transcription the DNA code is read, and in translation the code is used to build up protein molecules.
DNA is a triplet code. Each triplet, a group of three bases, codes for a specific amino acid.
Transcription
The DNA code for a remains in the , during transcription but a copy, called mRNA, moves from the nucleus to the where proteins are during translation in the . To make the mRNA the double stranded DNA unzips.
Translation
The mRNA leaves the nucleus and goes to the ribosomes.
Carrier molecules bring specific to add to the growing protein in the correct order. There are only about 20 different naturally-occurring amino acids. The protein produced depends on the template used, and if this sequence changes a different protein will be made.
Each protein has hundreds, or even thousands, of amino acids joined together in a unique sequence. It is then folded into a unique shape. This is very important, as it allows the protein to do their jobs, such as enzymes or hormones, and it can form structures within the body, such as collagen.
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Learn more about protein synthesis with Dr Alex Lathbridge.
Listen to the full series on BBC Sounds.
