3.10 Protein Synthesis: TRANSLATION

Question 1

What does tRNA stand for?

Answer 1

Transfer Ribonucleic Acid

Question 2

What does rRNA stand for?

Answer 2

Ribosomal Ribonucleic Acid

Question 3

What is tRNA (not what it stands for)?

Answer 3

A single-stranded nucleotide chain, folded up into a clover shape.

Question 4

Describe the process of translation.

Answer 4

• mRNA binds to ribosome
• A tRNA molecule with an anticodon that is complementary to the first mRNA codon binds with the mRNA
• The tRNA delivers the correct amino acid to the ribosome using the mRNA codon
• Each codon in mRNA is translated from 5’ to 3’, and the amino acids are joined by peptide bonds by peptidyl transferase
• The final polypeptide chain is modified and folded in the golgi apparatus

Question 5

What happens to the RNA molecules after protein synthesis?

Answer 5

They are degraded in the cytoplasm. Phosphodiester bonds are hydrolysed, RNA nucleotides are released and re-used.

Question 6

What is the anti-codon sequence of tRNA complementary to?

Answer 6

The codon on mRNA, and the amino acid attached to the tRNA.