Science Go to Huddersfield University
Science students last week visited Huddersfield University to carry out a practical as part of their Genetics and Genetic Engineering unit.
The aim of the activity was to compare areas of DNA known as ‘conserved DNA’ of different plant species. These areas of DNA enable geneticists to identify how closely related plant species are to each other and produce ‘evolutionary trees’.
These methods have identified that species that look completely different are in fact closely related to each other. For example, the Papaya is closely related to the Cabbage.
Here is what the science students got up to:
Students prepared a sample of plant DNA by first purifying discs containing the genetic material of either broccoli, spinach or basil (in order to remove any impurities).
They then added chemical reagents known as primers – these ‘cut’ the DNA strands to leave only the conserved DNA regions.
The DNA then multiplied using the polymerase chain reaction.
This first heats up the DNA to 95C to break the double helix. The mixture is then cooled to 56C to allow the primers to attach and cut the DNA. The mixture is then heated to 72C to allow the conserved DNA to be replicated. These processes can be repeated many times to multiply the DNA as much as required.
The DNA was then mixed with a loading dye and a DNA fingerprint was produced using gel electrophoresis. This was compared to a ‘DNA Ladder’ which tells us the size of the fragments present in the plant. If the size of the fragment is similar/the same – then the plants are likely to be closely related to each other.
Simon Reed, Science tutor, said: “The trip was great for the students as it allowed them to get really hands-on in a different, exciting environment. It links really well to what the students are currently studying so all-in-all, it was a fantastic day out.”