The synthesis of a polypeptide at a ribosome, using the sequence of triplets in messenger RNA to determine the order of the amino acids.

Where does translation take place?

At a ribosome, either free in the cytoplasm or attached to the rough endoplasmic reticulum.

A triplet of bases in messenger RNA that specifies one amino acid.

Describe the structure of a transfer RNA molecule.

A single strand of RNA folded into a clover-leaf shape held by hydrogen bonds, with an anticodon at one end and the site for a specific amino acid at the other.

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Biological Molecules

Topic overview Inorganic ions and the properties of water Monosaccharides and disaccharides Polysaccharides, storage and structure Lipids, triglycerides and phospholipids Amino acids and protein structure Condensation, hydrolysis and the food tests

Cell Structure and Organisation

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Nucleic Acids and Their Functions

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Nucleic Acids and Their Functions

Translation and the fate of the polypeptide

3 things to know
Component 1

Overview

Structure of a transfer RNA molecule and one gene, one polypeptide hypothesis.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

What is a codon?

Key term

What is an anticodon?

Key term

How does a transfer RNA molecule ensure the correct amino acid is added?

Questions from this subtopic

Each one with the model answer underneath.

1
What is translation?
Model answer
The synthesis of a polypeptide at a ribosome, using the sequence of triplets in messenger RNA to determine the order of the amino acids.
2
Where does translation take place?
Model answer
At a ribosome, either free in the cytoplasm or attached to the rough endoplasmic reticulum.
3
What is a codon?
Model answer
A triplet of bases in messenger RNA that specifies one amino acid.
4
What is an anticodon?
Model answer
A triplet of bases on a transfer RNA molecule that is complementary to a codon on the messenger RNA.
5
Describe the structure of a transfer RNA molecule.
Model answer
A single strand of RNA folded into a clover-leaf shape held by hydrogen bonds, with an anticodon at one end and the site for a specific amino acid at the other.
6
How does a transfer RNA molecule ensure the correct amino acid is added?
Model answer
Each carries only the amino acid corresponding to its own anticodon, and the anticodon can pair only with the matching codon.

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Translation and the fate of the polypeptide

Overview

What you need to know

What is a codon?

What is an anticodon?

How does a transfer RNA molecule ensure the correct amino acid is added?

Questions from this subtopic

What is translation?

Where does translation take place?

What is a codon?

What is an anticodon?

Describe the structure of a transfer RNA molecule.

How does a transfer RNA molecule ensure the correct amino acid is added?

Other ways to work this

What is inside Levo

See a huge jump in your memorisation

Cram a whole paper in one sitting

Blank Blitz consolidates the facts

Build It trains answer structure

Test It catches misconceptions

Brain Breaks between sessions

Every question in Nucleic Acids and Their Functions, on a schedule.