Over the past week in Biology, our class has been learning how the cell membrane transports molecules to and from the extracellular environment through diffusion and osmosis. To deepen our understanding of this unit, we conducted a practical investigation on how gummy bears absorb water. We left four gummy bears in different solutions of salt and water (e.g. 50ml water and 10g salt) and made predictions on how the gummy bears would change in size. After two days we measured the gummy bears and evaluated how they changed and what caused it. For example, a gummy bear left in a beaker of water had a +380% change in volume. We were able to determine that this was due to osmosis, where the hypotonic external environment makes the water diffuse down its concentration gradient into the gummy bear. We were also able to observe that when there is a higher concentration of water in the gummy bear, than in the beaker, the gummy bear shrinks and turns white. This is because the external solution has a lower water concentration, therefore is diffusing water out of the gummy.
This practical allowed me and other students to further understand how osmosis works by seeing it in real life. With the opportunities provided to us by Ms Milesi, we are able to thoroughly understand complex concepts while having fun. I am thoroughly enjoying Biology as a Year 10 student doing early VCE and would definitely recommend the opportunity to future students if you are leaning towards more science subjects and careers.
Joel Knight | Biology Student