Year 13 Biology Centre for Life Visit

I took 12 year 13 Biology students on a visit to the Centre for Life in Newcastle to analyse part of our genome using specialist equipment in the lab.

There is a gene that enables humans (and other closely related mammals) to taste a chemical called PTC which tastes very bitter. This compound is found in some green vegetables such as sprouts and cabbage. Students tasted a strip of paper containing this compound. Some could taste it, some couldn’t and some could hardly stand to have the paper in their mouth because it tasted so bad!

Students then took cells from inside of their mouth and extracted and amplified their DNA before using specialist restriction enzymes to cut out the gene (if they had it). Students then analysed their DNA using a technique called gel electrophoresis where it was visible under UV-light.

Some students found that they did not have either of the 2 alleles so couldn’t taste PTC, some found that they had 1 allele so could taste it slightly, some had both copies of the alleles and so had the ability to taste is strongly. There were, however, two students who realised that they were “super tasters”, where they didn’t have either allele but could taste PTC slightly!

After their lab work, students discussed the evolution of the gene and the importance of this in survival as it meant tasters didn’t eat toxic plants!

A really interesting day!

Mrs R Stevenson