What this practice covers
These questions are drawn from past CIE 9700 Biology papers and filtered to protein synthesis. You answer, you find out immediately whether you were right, and you get the reasoning for the correct option and for each distractor. Wrong answers go to a mistakes locker so you can come back to exactly those.
Practice is free. You need an account only so your progress and your mistakes are still there next time.
Start practising practice questions →
What examiners see students get wrong here
These are the errors that cost marks on protein synthesis, taken from our own topic notes. Read them before you practise and you will recognise the traps in the questions.
- Saying mRNA is complementary to the coding strand. It is complementary to the template strand and identical to the coding strand.
- Saying the anticodon is on the mRNA. The codon is on mRNA; the anticodon is on tRNA.
- Saying transcription happens at the ribosome. Transcription is in the nucleus; translation is at the ribosome.
- Saying tRNA "makes" the amino acid. It carries one that already exists in the cytoplasm.
- Saying the code is degenerate "because some codons are unused". Degeneracy means several codons code for the same amino acid.
Revise it first
If any of the above is unfamiliar, work through the notes before practising: Protein synthesis revision notes.