DrDAQ is a versatile instrument that connects to the USB port of any PC. Using the supplied PicoScope software it can be used as an oscilloscope, spectrum analyzer and signal generator.
Aerobic respiration is the process in which glucose and oxygen, through the action of enzymes in mitochondria, produce carbon dioxide, water and lots of energy. In this experiment the use of oxygen in the aerobic respiration of maggots can be seen in that, in a sealed container, the level of oxygen reduces with time.
A centrally heated and thermostatically controlled room or laboratory should not change much in temperature, probably only of the order of 2-3 °C, assuming that windows are not suddenly opened or lots of bunsen burners lit.
An extension to the experiment could be to place the trough, beehive shelf, beakers. maggots, etc into a thermostatically controlled heated water-bath, or on a hot-plate, and see if temperature affects the rate of respiration and so the speed of uptake of oxygen. Temperatures up to around 40°C are OK.
A further investigation could be to see if light intensity has any effect, illuminating the maggots with a light bulb and additionally recording the light level. One of the energy-saving fluorescent bulbs should be used so that little direct heating is caused. Readings should then be collected from the oxygen and temperature sensors connected to DrDAQ externally and from DrDAQ’s on-board light level sensor.
This experiment was written by Chris A Butlin of Sutton upon Derwent, UK.