A phyloGENETIC tree is not the same thing as a taxonomic tree, which is what Cal described. rRNA and molecular studies are used in phylogenetics to determine relations between species.
1 As the light intensity increases, the rate of photosynthesis increases. 2  However, the rate will not increase beyond a certain level of light intensity. 3  At high light intensities the rate becomes constant, even with further increases in light intensity, there are no increases in the rate.
The students can be allocated to investigate a particular factor that affects the rate of photosynthesis, or they can choose from this list, or they can develop their own ideas. 1  Light intensity or distance of the Elodea from the lamp. ( 2 Light intensity is proportional to 1/distance 2. 3  Temperature of the water.