A Level biologists explore the genetic code.
It’s been another industrious and hands-on week for students working towards A Level Biology under the guidance of Mr Matanda.
In one lesson, he set the girls the task of making a double helix – from jelly babies and cocktail sticks no less – to find out about the shape of DNA.
With the four colours of sweets representing the four kinds of DNA letters, the girls had to work out which jelly babies would bind with each other. Once they knew and understood the sequence of one strand, they could then work out the sequence and build another sweetie DNA strand.
They poked toothpicks through the head and feet of the jelly babies and paired the sweets together, again with toothpicks, gradually building up a ladder and always obeying the colour rules. The final stage was to connect the left hand and the right hand of the ladder and give it a twist to complete the double helix.
In another class, the objective for students was to extract DNA from peas. Following instructions, they combined pea pulp with salty washing up water, cooled the mixture in an ice bath, then added ice-cold ethanol. The experiment saw nucleic acids (DNA and RNA) rise to the top of the solution, isolating them from the peas below.