Protein Synthesis Flashcards

All 6 cards in this deck

How does the order of bases in a gene decide the protein that is made?

The order of bases decides the order of amino acids, and the amino acid chain folds to give a specifically shaped protein, e.g. an enzyme.

Where does RNA polymerase bind at the start of transcription?

To non-coding DNA located in front of the gene.

What does RNA polymerase do in transcription?

It produces a complementary mRNA strand from the coding DNA of the gene.

What is a codon?

A triplet of bases in mRNA that codes for one specific amino acid.

What are the steps of translation?

e.g. an mRNA strand made from the gene for an enzyme

1. The mRNA attaches to a ribosome.
2. tRNA transfers amino acids to the ribosome, matching each codon of the mRNA.
3. The amino acids are linked together to form a polypeptide – here, the enzyme.

How do you work out how many amino acids a length of mRNA codes for?

e.g. an mRNA strand of 12 bases

1. Each amino acid is coded for by a triplet of bases (one codon).
2. Divide the number of bases by 3: $12 \div 3 = 4$ amino acids.