Testing the Photosythetic Needs of Plants By: Jenna Cossey Undergraduate TTU Secondary Education Major Emphasis- Biology

Introduction Can plants survive better in natural sunlight or in artificial light? Can plants survive better in natural sunlight or in artificial light? Test two groups of plants: one grown in artificial light, one grown in natural sunlight. Test two groups of plants: one grown in artificial light, one grown in natural sunlight. To accomplish this I will grow one group of plants indoors with no access to natural sunlight, and grow one group of plants in a window sill. To accomplish this I will grow one group of plants indoors with no access to natural sunlight, and grow one group of plants in a window sill. I expect that the group of plants with access to natural sunlight will grow better. I expect that the group of plants with access to natural sunlight will grow better. My hypothesis is that plants with grow most efficiently in natural lighting conditions. My hypothesis is that plants with grow most efficiently in natural lighting conditions. My null hypothesis is that plants will grow bettter in artificial lighting conditions. My null hypothesis is that plants will grow bettter in artificial lighting conditions.

Literature Citings  Chaney, William R Does Night Lighting Harm Trees? 17.pdf 17.pdfwww.ces.purdue.edu/extmedia/FNR/FNR-FAQ- 17.pdf  Farabee, M.J What is Photosynthesis? PS.html_rpmi.htm PS.html_rpmi.htm PS.html_rpmi.htm  Taylor, Maxine  Rothenberger, Ray R Lighting Indoor House Plants.  Vermaas, Wim ointro.html

Photosynthetic Process A simple diagram: Carbon Dioxide + water + photons => glucose + oxygen Carbon Dioxide + water + photons => glucose + oxygen

Light Sources Sunlight Sunlight Incandescent Light Incandescent Light

WHICH SOURCE? In order to determine which source of light best facilitates photosynthesis, I experimented with two test groups, one grown in each source of light ( artificial, natural) and recorded the growing patterns of each.

Hypothesis Hypothesis: Plants exposed to more natural light will grow more efficiently. Hypothesis: Plants exposed to more natural light will grow more efficiently. Null: Plants exposed to more artificial light will grow more efficiently. Null: Plants exposed to more artificial light will grow more efficiently.

Experimental Design Step 1: State the Problem. Which source of light best facilitates photosynthesis? Step 2: Research the Problem. Test a group of plants in artificial light and test another group of plants in natural light. Plants need light to grow, but what kind? Step 3: Form a Hypothesis. Plants exposed to more natural light will grow more efficiently. Step 4: Test the Hypothesis. To test this hypothesis I will test the growth of plants in both natural and artificial lighting conditions. And record their growth rates. Step 5: Draw Conclusions from the data. The growth rate data will either prove or disprove my hypothesis.

How will I know? In order to determine which source of light the plants use best I used both quantitative and qualitative analysis.(Vermaas 2007) In order to determine which source of light the plants use best I used both quantitative and qualitative analysis.(Vermaas 2007) I measured the height of the plants at different intervals of growth. I measured the height of the plants at different intervals of growth. I counted the number of plants growing at different intervals, as well as the number of leaves/flowers on each plant. I counted the number of plants growing at different intervals, as well as the number of leaves/flowers on each plant.

Results? I expected that the plants with access to the natural sunlight would grow best. I expected that the plants with access to the natural sunlight would grow best. I also expected that the plants in artificial light would grow, but not as abundantly. I also expected that the plants in artificial light would grow, but not as abundantly. I confirmed my hypothesis and rejected my null hypothesis. I confirmed my hypothesis and rejected my null hypothesis.

Week 1 Place the plants in their areas to grow and record starting data. Week 2 Observe and record any changes in the plants Week 3 Count and measure plants and record the data. Week 4 Observe and record any changes in the plants. Week 5 Observe and record any changes in the plants. Week 6 Count and measure the plants and record the data. Week 7 Observe and record any changes in the plants. Week 8 Observe and record any changes in the plants. Week 9 Final measurement and counting of plants.

Discussion Experiment confirmed the results of previous experiments.( Rothenberger 1993) Experiment confirmed the results of previous experiments.( Rothenberger 1993) This allowed me to draw my conclusions. This allowed me to draw my conclusions.

Final Discussion My results rejected my null hypothesis and confirmed my alternative hypothesis. My results rejected my null hypothesis and confirmed my alternative hypothesis. The plants lighted with natural sunlight grew more efficiently. The plants lighted with natural sunlight grew more efficiently.