
Light Color and Elodea Oxygen Production
Medium
Does the color of light change how much oxygen an aquatic plant makes? Elodea is a water plant that releases oxygen during photosynthesis (the process plants use to turn light into food). You place elodea strands under five colors of light:
- Red
- Blue
- Green
- Yellow
- White
Each color is created by hanging colored cellophane in front of a lamp. You capture the oxygen in a graduated cylinder and measure it after 16 hours. Red and blue light each produced 1 mL of oxygen. White light matched that amount. Yellow produced half as much. Green produced no measurable oxygen at all.
Hypothesis
The hypothesis is that elodea will produce the most oxygen when living in blue light.
Method & Materials
You will separate the elodea plants into five groups, each with a different color of light. You will measure the amount of oxygen produced by the elodea plants and record the results.
You will need a 250 ml beaker, a 25 ml graduated cylinder, a clamp, a ring stand, a large waterproof container, 10 strands of elodea, a light meter, four circles of colored cellophane, four hangers bent into circles, a lamp, a 60 watt light bulb, and tap water.
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See what’s includedResults
The results showed that the red, blue, and white light produced 1 ml of oxygen, while the yellow light produced 0.5 ml of oxygen. The green light produced no measurable amount of oxygen. This supports the hypothesis that elodea will produce the most oxygen when living in blue light.
Why do this project?
This science project is interesting because it can teach us how colors of light have different effects on photosynthesis.
Also Consider
Experiment variations to consider include testing the effects of different intensities of light or testing the effects of different lengths of time the light shines on the elodea plants.
Full project details
Additional information and source material for this project are available below.Related video
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
Not only is this variation of the experiment fascinating, but it also uses rainbow-colored test tubes that can be reused as a beautiful vase set for flowers once the experiment is over!
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