A r c h i v e d I n f o r m a t i o n
Plants are the only things on earth that turn sunlight into food. They do it through a process called photosynthesis, which is explored in this activity.
What you'll need
Some household plants
A book on plant care from a store or the library
Your magnifying glass
Your science journal
What to do
Photosynthesis means to "put together using light". Plants use sunlight to turn carbon dioxide from the air, and water into food. Plants need all of these to remain healthy. When the plant gets enough of these things, it produces a simple sugar, which it uses immediately or stores in a converted form of starch. We don't know exactly how this happens. But we do know that chlorophyll, the green substance in plants, helps it to occur.
- Look in your plant-care book, or ask a grown-up, to find out how much water each plant needs. Some may need to be watered more than others.
- Take two clippings from one plant. Put one in a glass of water. Put the other one in a glass with no water. Check each day to see how long the one without water can survive.
- Water the rest of the plants each week for several weeks. Fertilize some of the plants but not others during this time. Label the ones you fertilized.
- Record the following in your science journal for those plants that got fertilized and for those that didn't:
Did any of the plants start to droop?
Did any of the plants have yellow leaves that fell off?
Did the plants grow toward the light?
- See what happens when a plant (or part of a plant) doesn't get any light:
Cut 3 paper shapes about 2 inches by 2 inches. Circles and triangles work well, but you can experiment with other shapes, too.
Clip them to the leaves of a plant, preferably one with large leaves. Either an indoor or an outdoor plant will do. Be very careful not to damage the plant.
Leave one paper cutout on for 1 day, a second on for 2 days, and a third on for a week.
How long does it take for the plant to react? How long does it take for the plant to return to normal?