The following activity is good to explain how RNA and DNA work together to make protein.

Give a string of letters composed of a mix of Cs, Gs, As and Ts to one pupil, who stands in a circle drawn on the floor of the classroom (the nucleus of the cell).

This pupil represents DNA. Another pupil goes to the DNA and writes down the series of letters, but translates them so they become RNAs (so the nucleic acid C becomes G, G becomes C, A becomes U and T becomes A).

This pupil is the messenger RNA, known as MRNA. They take the new string of letters out into the classroom (the cell cytoplasm) and another person - the ribosome - translates the code back.

The pupils then cut off the first three letters of the strip. They translate this into a single letter - the equivalent of an amino acid - based on a code I have given them.

The cutting and decoding continues until it spells out a short message, which is the protein.

One string of 24 letters I give pupils becomes eight letters which spell out “well done”.

We are then able to discuss the fact that a small error anywhere in this whole process can lead to the meaning of the message being changed.

By having the pupils physically moving around the room and working with code sheets, they seem to understand the process a lot better and also understand the different places in which mutation can occur Stephanie Sutherland is a science teacher at Tarbert Academy, Tarbert, Loch Fyne, Scotland

CURRICULUM OBJECTIVES COVERED BY THE LESSON INCLUDE:

* The lesson covers the topic of inheritance, which appears in AS and A-level exams and Highers in Scotland.

* The QCA subject criteria for AS and A-level biology states it must cover how “genes incorporate coded information which determines the nature of organisms”.

This should include the basic structure and role of RNA and DNA and the nature of genetic code.