Natwerk Designs

How can I design a controlled experiment to test how light in a visible spectrum can a healthy plant utilize?

i'm learning about photosynthesis in biology and this is one of the essays. please please please help me with this and maybe even contact me with more information so I don't fail this test. thank you.

Public Comments

1. Traditionally, the experiment is run with a spectroscope or a spectrometer. A leaf extract of the plant's leaf pigments. Once the pigments have been extracted, a dilute solution of the pigments are placed in the path of the light entering the spectroscope. You should see a color spectrum from violet to red. The tube of pigment extract is placed in the beam of light. Examination of the spectrum while reveal black bands in spectrum where the light is being absorbed completely. Those missing colors being most strongly absorbed would drive the photosynthesis in the plant. If that is not possible, you could grow the plants in different colors of light using colored cellophane to block the other colors. Plants grown in white light (natural sunlight) would be your control to compare the growth of the plants. The best measure of growth would be to carefully harvest the plants removing all the growing medium, dry the plants in a low heat oven to remove the water, and record the dry weight of the plants. The color producing the best growth should be indicated by the heaviest weight of the plants.