Aug 202013

photo by Hbreton19

Students often have misconceptions about the process of decomposition.  Students often explain decomposition as a purely physical process.  This introductory activity is meant to display the biochemical process of cellular respiration as it is occurring in microorganisms present in composting material. Cell respiration refers to the process of converting the chemical energy of organic molecules into a form immediately usable by organisms. Glucose may be oxidized completely if sufficient oxygen is available according to the following equation:

C6H12O6 + 6O2  –>  6 H2O + 6 CO2 + energy

All organisms oxidize glucose for energy. Often, this energy is used to convert ADP and phosphate into ATP. Using the CO2 Gas Sensor and O2 Gas Sensor, students will monitor the carbon dioxide produced and the oxygen consumed by bacterial and fungi during cell respiration.