Demonstrating Oxygen Evolution during Photosynthesis using Pondweed Demonstrating Oxygen Evolution during Photosynthesis using Pondweed Watching gas bubble up from a pondweed as it photosynthesises can be a great demonstration or student practical.
Have your child collect large leaves from the same tree type.
You and your child should tear or chop the leaves into very small pieces and put them into small jars. Add enough rubbing alcohol to the jar to cover the leaves. Using a plastic knife or spoon, carefully chop and grind the leaves in the alcohol.
Use in a well-ventilated area, and avoid contact with skin. Have your child cover the jar very loosely with a lid, plastic wrap or aluminum foil. Place the jar carefully into a shallow tray containing 1 inch of hot tap water.
Keep the jar in the water for at least a half-hour, longer if needed, until the alcohol has become colored the darker the better.
Twirl the jar gently about every five minutes. Replace the hot water if it cools off. Have your child cut a long thin strip of coffee filter paper. Remove the jar from the water and uncovered. Place a strip of filter paper into the jar so that one end is in the alcohol.
Bend the other end over the top of the jar and secure it with tape. The alcohol will travel up the paper, bringing the colors with it. After minutes the colors will travel different distances up the paper as the alcohol evaporates.
Your child should be able to see different shades of green, and possibly some yellow, orange or red, depending on the type of leaf. Chlorophyll is a green compound that hides the other colored pigments present in leaves.
In the autumn chlorophyll breaks down, allowing the other pigments to be seen. The mix of pigments in a leaf may be separated into bands of color by the technique of paper chromatography.
Chromatography involves the separation of mixtures into individual components, which you just did using alcohol and energy heat. Then, by "absorption" and "capillarity," separation can take place! The paper holds the substances using absorption, while capillarity pulls the substances up the paper at different rates.
Pigments are separated on the paper and show up as colored streaks or bands. Why do ants like sugar? Do ants like artificial sweeteners too? Kids find out with this great inquiry-based science fair project.// Provide alternate content for browsers that do not support scripting // or for those that have scripting disabled.
This virtual experiments require Adobe Flash. Fingerprint: Fingerprint, impression made by the papillary ridges on the ends of the fingers and thumbs. Fingerprints afford an infallible means of personal identification, because the ridge arrangement on every finger of every human being is unique and does not alter with growth or age.
Fingerprints serve to. It is fairly easy to show that plants produce oxygen and starch in schwenkreis.com age 14–16 students may have collected the gas given off by pond weed (for example Elodea) and tested leaves for starch.. It is not quite so easy to demonstrate the other reactions in photosynthesis.
BioCoach Activity Concept 3: The Action Spectrum for Photosynthesis.
A classic experiment reveals which wavelengths work best for photosynthesis. BioCoach Activity Concept 3: The Action Spectrum for Photosynthesis.
A classic experiment reveals which wavelengths work best for photosynthesis. Photosynthesis is one of the fundamental aspects of biology. You can do this fun photosynthesis experiment using leaf discs to better understand how it works.