Attribution: This is a cached copy of a third party project. Many of these sites are from 20 years ago and the majority are no longer running. We show only the first page of the project. We do not save all pages since copyright belongs to the third-party author.
Purpose: What is the effect of light and dark on seed germination? K-6 Materials: unflavored gelatin (such as Knox Unflavored Gelatine ®) 3% hydrogen peroxide (usual strength right from the bottle),91% isopropyl alcohol liquid house plant food (such as Miracle-Gro ®),disinfecting hand soap household disinfectant tap water seeds (such as radish, mung bean, lima bean, green bean, alfalfa, and corn) clear, tall jars with lids (baby food, Snapple ® or other taller jars) 2 or 4 cup measuring cup forceps or tweezers spoon, glass rod, or other stirring instrument transparent tape aluminum foil Experiment: 1. Clean 6 or 8 baby food or Snapple ® jars. For this quick setup you can wash jars and lids by hand with soap and water. Then swirl 91% alcohol around in the jar and wipe jar and lid with a clean, alcohol moistened paper towel. Let jar air dry upside down on the lid. You may get some microbial contamination, but you will also see how quickly you will get results with the seeds. 2. Mix 2 packages of gelatin with 1 1/2 cups of water in a 2 cup measuring cup and microwave it for 30 seconds after it starts to boil. 3. Let cool slightly and swirl the measuring cup to finish mixing. 4. Pour gelatin into 6 or 8 jars to a level of about 3/4 inch. 5. Add 3 drops of liquid fertilizer to each jar and swirl to mix it. 6. The gelatin will set up at room temperature in about 6 hours or overnight. 7. Disinfect radish seeds in 3% hydrogen peroxide for 15 minutes and place on the gelatin with forceps rinsed with alcohol. 8. Remember to open the jars only briefly for each seed as described earlier. Seeds will germinate in less than 24 hours and stems will grow 1 inch in 2 or 3 days at a warm room temperature. 9. Set up 2 jars with 6 seeds each on the gelatin. 10. Wrap 1 jar in aluminum foil but do not cover the lid with foil so air can be exchanged. 11. Do not wrap the other jar. 12. Place them side by side where they will have a warm temperature and indirect sunlight. 13. Check them each day to compare how and when they germinate. Make a chart to write in the daily observations or draw a picture. Radishes (and most of the other seeds listed) germinatein less than 24 hours so they will get results very quickly. Once they have determined whether or not light is necessary for germination, they can continue to make observations for several days to see if the new plant needs light to continue to grow and make food. They should make daily observations of leaf color as well as stem length in each jar every day. Then record the results and take an average. They can make a graph of the data, Y= height of stem and X= number of days. Results: Seeds germinated in the light and in the dark. The stems in the dark grew the tallest. The leaves in the light were more green. Conclusion: The seeds can germinate both in the light and in the dark. The plants in the dark are looking for light so they grew taller. The leaves in the light photosynthesize so they were more green.