Ap Biology Photosynthetic Organism Free Response Essay
632 WordsDec 20th, 20103 Pages
The rate of photosynthesis may vary with changes that occur in environmental temperature, wavelength of light, and light intensity. Using a photosynthetic organism of your choice, choose only ONE of the three variables (temperature, wavelength of light, or light intensity) and for this variable.
• Design a scientific experiment to determine the effect of the variable on the rate of photosynthesis for the organism
• Explain how you would measure the rate of photosynthesis in your experiment
• Describe the results you would expect. Explain why you would expect these results. The rate of photosynthesis is affected by environmental factors like light intensity, light wavelength, and temperature. This experiment will test the…show more content…
The rate of photosynthesis can be determined different ways. Because oxygen is a product of photosynthesis and the Elodea plant is submerged in water, the oxygen is released in bubbles that rise to the surface of the water in the beaker. In this experiment, the rate of photosynthesis for each degree of light intensity can be measured by counting the number of bubbles released every 30 seconds for five minutes at each distance. The rate is the number of bubbles released per minute.
Organisms that use the process of photosynthesis to create sugar to use for energy have a greater rate of photosynthesis when the intensity of the light source is the greatest. If light is far away from the leaves of a plant, for example, then it takes more time for the light to be absorbed and used in photosynthesis. When it takes more time for the light to reach the leaves, the rate of photosynthesis decreases. As the light intensity increases, I would expect the rate of photosynthesis to increase as well. Therefore, I would expect that when the Elodea is closest to the light bulb, the rate of photosynthesis would be the greatest. My hypothesis would be: If light intensity affects the rate of photosynthesis, and the rate of photosynthesis is measured using the amount of