QUESTION 5 (4 marks)
Explain the process of protein synthesis in terms of transcription and translation.
QCAA guide · typeset solution
QCAA sample response and mark allocation
5 | Transcription involves copying a gene’s DNA sequence to make an RNA molecule. This is performed by enzymes called RNA polymerases, which link nucleotides to form an mRNA strand. In the translation process, the mRNA formed in transcription is transported out of the nucleus to the ribosome. Here, it directs protein synthesis. The mRNA passes through the ribosome and tRNA interacts with it, adding amino acids together to make a protein chain. | • states that in transcription DNA is copied [1 mark] mRNA is formed [1 mark] • states that in translation mRNA is transported to ribosome [1 mark] tRNA adds amino acids to form a protein chain [1 mark] | ||
QCAA sample response and marking criteria reproduced from the official guide.
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