Photosynthesis And Cellular Respiration Lab Report

This lab was split up into two different experiments, using different variables in each. During the first section of the lab, we investigated the what the effect of light is on both photosynthesis and cellular respiration. Our hypothesis about this effect was that the cuvette representing ‘no light’, being covered in foil, would result in a yellow CO2 indicator fluid, meaning that there was a decrease in pH and a high level of CO2 was present. Additionally, we hypothesized that the cuvette that was exposed to light would result in a purple CO2 indicator fluid, meaning that there was an increase in pH and a high level of O2 was present. Both parts of this hypothesis were fully supported. In this first experiment, the indicator fluid in either environmental variable, light or dark, was an
These measurements supported the claim that, after exposure to light, pH levels of the cuvette will increase, indicating an increased level of O2, while a lack of light will cause pH levels to drop, indicating an increased level of CO2. This pH level trend was consistent over the observed 45 minutes of this experiment, as seen in Table 1 and Graph 1. By the this 45 minute marker, the pH indicator of the light-exposed cuvette measured at 9.1 and the dark at 6.9, the lowest possible value that we could observe from the provided scale. The change in pH and O2 and CO2 levels is due to both photosynthesis and cellular respiration occuring within the algae beads. The former, photosynthesis, is the process, done by plants, of converting light energy into chemical energy, while the latter, cellular respiration, is the process, done by all organisms, of converting chemical energy, produced by plants, into an energy that may be used to run an organism's metabolic