CO2 (gas) sensor (low range)

In this activity students investigate whether plants also respire. Most people know that animals respire but what about plants? By making use of germinating seeds, and a CO2 sensor, the respiration of plants seeds can be measured. Activity Respiration of plant seeds (demo)
In this activity students examine the photosynthesis. Using an O2 sensor to measure the rate of photosynthesis at different light intensity. How much disadvantage has a plant in the shade anyway? Activity Photosynthesis (light intensity) (demo)