I am familiar with the apparatus used in this experiment as I have used it before to demonstrate respiration. As the maggots in the test tube are taking in oxygen they produce carbon dioxide. This Co is absorbed by the sodalime in the test tube. At this time pressure in the test tube will drop, drawing the red Eosin dye up the respirometer. How far the dye is drawn up will depend upon the rate of the maggots respiration. The distance the dye has moved will be measured using a ruler and recorded.
I am hoping to see the dye move along the tube so I can use this as evidence. My Year 10 notes tell me that as the temperature increases enzyme activity should also increase. At around 40°C enzymes become denatured so the respiration reaction would cease. I believe that as the temperature rises by 10°C the rate doubles.
There are some variables that must be controlled if I am to obtain valid evidence. The first is the mass of the maggots. The larger the mass of the maggots and the more maggots there are the more respiration will take place. The mass of the maggots must be kept constant. Secondly, the mass of the sodalime must also be kept constant. This is because more sodalime will absorb more carbon dioxide produced by the maggots so the pressure will drop faster.
The distance the Eosin dye has moved up the tube in a certain time will be measured. I have selected these temperatures: 0°C, 10°C, 20°C, 30°C, 40°C and 50°C.
These temperatures have been selected so that a precise graph can be drawn with an expansive range of results. Each temperature will be repeated twice to eliminate anomalous results.
Qualitively I predict that as the temperature increases the rate of reaction will increase due to enzyme activity escalating. Quantitively I predict that with a 10°C rise in temperature the rate will double. The results can be used as evidence in the form of a graph. With a good range of temperatures the results will be accurate.
