Cellular Respiration

Transpiration of oxygen and water out of the stomata of leaves was evident in the plants found in the outdoor classroom this week.  Sixth graders placed a plastic bag around a leaf and left it for 24 hours.  When they returned to check on the project, most students found between 2.5 and 5 ml of water in their bag. This process proved that cellular respiration had taken place in the cells of the chosen plant.  

In cellular respiration, the mitochondria in cells convert small glucose molecules into energy, carbon dioxide, and water. This process is the other half of the energy cycle. Photosynthesis and cellular respiration are the two processes in the energy cycle. 

Students also completed a chromatography investigation where they took leaves from some of the green plants and placed them in alcohol.  After allowing the chlorophyll to break down, they placed a filter into the solution to separate the chlorophyll from the other colors in the leaf.  The fall leaf colors have been in the leaves throughout the growing season, we have not been able to see them because of the chlorophyll.  When plants start to go dormant for the winter, the chlorophyll breaks down and the other colors begin to show. 

Students were able to study the leaves at both the macro and micro scale by using the digital microscope with an ipad.