Year 12 Biology 

Year 12 Biology students used algae balls to investigate the effect of light intensity on photosynthesis. The algae balls were placed in an indicator solution. As photosynthesis occurs, it uses the carbon dioxide in the solution causing it to change pH. We can observe this by the colour change in the indicator solution. The first vial was kept in the dark, the subsequent vials were moving away from the light source at 25cm increment. This demonstrates that the highest levels of photosynthesis occurred closest to the light source.

Students also investigated how the concentration of glucose influences the rate of cellular respiration in yeast. They did this by measuring the height of displacement of liquid due to the production of carbon dioxide gas.

Sarah Beattie

Science Domain Leader