Sahlea TubbehPeriod 2I. Title: Plant Growth with and without Light II. Introduction: Plants are the most important thing on the planet. They provide oxygen for animals and humans and cleanse the air though an important process called photosynthesis. Thisexperiment tests if pinto bean seeds germinate better in the light or in the dark. Germination is the beginning of the development of the embryo into a new plant. Before the seed begins to germinate it is in state of dormancy, or inactivity. Dormancy ends when the seed is in a favorable temperature (25 degrees Celsius to 30 degrees Celsius) and has absorbed a sufficient amount of water and oxygen.There are many steps the seed goes through in the process of germination. The first step is when the outer shell of the seed opens. The second step is when the part of the seed, called the radicle, grows down into the soil and develops into the root. The hypocotyl (part of the stem thatis nearest to the seed) also emerges and grows into the soil and forms what is called the hypocotyl arch. When the hypocotyl emerges from the soil, it becomes straight because it has been exposed to the light. When the plant is exposed to the light, then the chlorophyll in the leaves will be able to perform photosynthesis.Cotyledons also play an important role in the process of seed germination. A cotyledon is thestructure in the embryo of the seed that stores and absorbs food for the developing plant before it can perform the process of photosynthesis. Cotyledons protect the structure in the plant called the epicotyl. When the hypocotyl emerges from the soil, the cotyledons spread apart, exposing the epicotyl which contains two primary leaves and the apical meristem. The apical meristem produces cells for the developing plant. When the energy stored in the cotyledon runs out, the plant must be able to perform the process of photosynthesis. The equation for photosynthesis is 6CO2 + 6H20 + ENERGY  C6H12O6 + 602. Glucose is made from this reaction and will 1Sahlea TubbehPeriod 2later be used in another reaction called cellular respiration. The ATP that is formed through cellular respiration gives the plants energy to perform mitosis and move their roots to find sources of water.III. Purpose/Problem: What Effect Does Light Have On Pinto Bean Seed Germination?IV. Hypothesis: If seeds get a sufficient amount of light, then they will germinate.V. Materials: Potting Soil2 4 inch Pots8 Pinto Bean SeedsWater1 RulerVI. Procedure:1. Plant the pinto bean seeds 1 inch deep in potting soil. 2. Place 4 seeds in the pot labeled “light” and 4 in the pot labeled “dark.”3. Place the “dark” pot in a dark area that receives no sunlight. Place the “light” pot in a light that receives approximately 8-11 hours of sunlight per day.4. Water each pot with 50 milliliters of water every 2 days for 1 month. 5. Measure plant growth every day in millimeters.6. Record plant growth data in a data chart.VII. Data: The data shown below in Table 1 and Graph 1 show the results from the pot with the pinto bean seeds growing in a window and getting 8-11 hours of sunlight per day and another potwhich was placed in a dark closet getting no sunlight per day. 2Sahlea TubbehPeriod 2 Table I: Height of Pinto Bean Seeds Grown in the Light and the Dark over Time DateNo Light (height of plant in mm) Light (height of plant in mm)13-Jan soaked soaked14-Jan planted planted24-Jan sprouted sprouted25-Jan 5 526-Jan 50 727-Jan 65 728-Jan 119 1929-Jan 180 4030-Jan 210 9031-Jan 250 1001-Feb 305 1102-Feb 310 1253-Feb 330 1324-Feb 343 1395-Feb 358 150Graph I: Height of Pinto Bean Seeds Grown in the Light and the Dark over Time13-Jan24-Jan26-Jan28-Jan30-Jan1-Feb3-Feb5-Feb050100150200250300350400Light (height of plant in mm)No light (height of plant in mm)3Sahlea TubbehPeriod 2VIII. Results: This experiment was designed to test whether or not the amount of light had an effect on pinto bean seed germination. A total of eight pinto bean seeds were used, four in a lightspace which were by a window, and 4 in dark space which were in a closet. The height of each plant was recorded over the period of fourteen days. In the beginning of the experiment, both plants were growing at the same rate until day five when the plant that was in a closet began to grow more quickly with a height of 50 mm. while the seeds grown in the light had only gotten to 7 mm. on the same day. Overall, the pinto bean seeds that were in the closet germinated more quickly and, in the end, were the tallest at a height of 350 mm. However, the pinto bean seeds that were in the light did germinate and by the end were 150 mm, 200 mm shorter than the seeds that were grown by a window, but they were significantly healthier and less pale than the plant inthe closet. Therefore, this experiment showed that light did have an effect on seed germination, by significantly changing the health of the plant. IX. Conclusion: The data from this experiment shows that light did have an effect on pinto bean seed germination. The data shows that plants need light in order to germinate more successfully. The plant that was placed by the window began growing more slowly and was shorter at the end of fourteen days than the plant that was placed in the closet, but it was healthier, greener in color,and had more leaves. Although the plant that was placed in the closet did germinate and was taller than the plant in the window, it was pale in color and had no leaves. This may be because the plant that was placed in the closet could not perform photosynthesis, which happens in the leaves and therefore could not provide the adequate energy for the plant to grow as well because sunlight is needed for photosynthesis.My hypothesis was if seeds get a sufficient amount of light, then they will germinate and this was not correct. I hypothesized that the plant in the closet would not germinate at all, but it 4Sahlea TubbehPeriod 2did germinate and it did grow, however, plants do need a sufficient light source in order to grow successfully and for the plant to be at its’ best health, this was exemplified by the appearance andhealth of the plant grown by the window and the pale and unhealthy plant grown in the closet.The problem in this experiment was resolved. I learned that light does have an effect on seed germination in a way that I did not quite expect. I did not think that plants could germinate without a light source, and while