Translation and the Genetic Code
Ribosomes read mRNA codons to build proteins.
About this topic
In translation, ribosomes read the mRNA in groups of three bases called codons, each specifying an amino acid. Transfer RNA (tRNA) molecules carry amino acids and match their anticodons to codons, and the ribosome joins amino acids into a polypeptide chain until it reaches a stop codon. AUG is the start codon.
The code is nearly universal and redundant, since 64 codons encode 20 amino acids. The protein then folds into its functional shape.
Take the mRNA sequence AUG GCU UAA. AUG is the start codon and codes for methionine, GCU codes for alanine, and UAA is a stop codon, so the peptide is just two amino acids. There are 64 possible codons but only 20 amino acids, so the code is redundant: several codons code for the same amino acid, which gives some protection against mutations.
The code is nearly universal across life, which is why bacteria can make human insulin when given the human gene. Ribosomes move along the mRNA, and the finished chain folds into a functional protein. Students often confuse codon and anticodon: the codon is on mRNA, the anticodon is on tRNA and pairs with it.
Key ideas
- Three bases = one codon
- tRNA brings amino acids
- AUG starts, stop codons end
Quick check
Use cases: where Translation and the Genetic Code helps
- Homework: review the key idea behind Translation and the Genetic Code before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Translation and the Genetic Code without notes.
- Visual learning: play with the interactive lab to see how Translation and the Genetic Code changes when you adjust its inputs.
- Teaching a friend: explain Translation and the Genetic Code in your own words, then compare your version with the key ideas.
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Frequently asked questions
What is Translation and the Genetic Code?
Ribosomes read mRNA codons to build proteins.
What will I learn in Translation and the Genetic Code?
Three bases = one codon. tRNA brings amino acids. AUG starts, stop codons end.
Is Translation and the Genetic Code part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Translation and the Genetic Code lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Translation and the Genetic Code?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.