In the final week before Half Term, the Senior School welcomed Year 5 for a day of exploration. The boys began the morning with a welcome from Mr Manley, Lower Master and Head of Year 7, who spoke about the spirit of discovery. He encouraged the boys to be open-minded, to get involved and to make the most of what the day would offer.
With lab coats, eye protection and gloves on, the boys grabbed a tray which contained strawberries, scissors, test tube, plastic bag, muslin bag, funnel, detergent, salt and cotton bud stick. By following the instructions, the practical activity was a useful way to appreciate the presence of DNA in living cells. The boys started off the activity by massaging the strawberries – albeit a bit nervous about breaking the bags – breaking down the cell walls, membranes and nuclei to release the DNA. The next step involved cutting the plastic bag to release the liquid into a funnel lined with muslin. While waiting for the strawberry liquid to drop down into the test tube, a quick quiz filled the wait.
Do you know about DNA?
When was it discovered? 1953
Which scientists were credited? Watson & Crick
Which university were they working at? Cambridge University
Fun fact: Strawberries are octoploids, meaning they have eight sets of chromosomes.
The next step involved the teacher pouring ice cold ethanol gently onto everyone’s pink filtrate in their test tubes which formed a clear upper layer in the tube. The boys watched patiently as strands of white DNA began to precipitate between the two layers and eventually float off the into the upper layer. Inserting the cotton bud stick into the test tube the boys extracted out the white gooey DNA strands holding up their experiment in amazement.
Thank you to the Biology Department for helping run the sessions!
