Leaf experiments for kids first: Why water runs off of some leaves?
On some pages, we see nearly spherical water droplets that drip off the surface - what’s it all about?
Water droplets that are left to themselves, form a spherical shape. Perhaps you’ve ever seen pictures of astronauts in space, press the small amounts of water from a returnable bottles: float through the space station, small or largebeads. Cause of this behavior is the so-called surface tension. It ensures that water drops to shrink their surface.The same goes best with a ball.
Now the water droplet hits on leaves of certain plants, for which there is a water-repellent surface, it may not wet thesurface. He remains more or less pronounced, flattenedball on the leaf. Often, these pearl drop very easily and take it with other, smaller droplets or small dust grains. This effect is also called ”lotus effect” on lotus leaves becausethere is a particularly large Wasserbweisung.
For children it may be interesting times to sprinkle the leaves of various plants with water and observe what plantshave a lotus effect.
Leaf experiments for kids second: Why does the color yellow-red leaves of our trees in autumn?
In the fall of our nature will enchant you with gorgeouscolors - what does this have to do with “chlorophyll”?
This makes chlorophyll, along with other materials for thecollection of solar energy in the leaves. The sun shineswith a whole spectrum of colors to us, and most areswallowed by the chlorophyll, so to speak. Only green colorof chlorophyll can not aborbieren, these color componentsof sunlight are therefore reflected away from the leaves inall directions and we see them.
In autumn, the weather changes every day in our districtsfor the trees. It’s getting colder, the less sunshine. The trees (except for the evergreen conifers) are preparing to shed their leaves. Throughout this period, the influence of chlorophyll and other materials back, just the ones that shine so great, come forth now. It is believed that the redcolor signal to discourage predators. But the opinions arequite apart here.
Nevertheless, this phase of the beautiful autumn colorsshould be utilized for long walks, where children gather thefallen leaves and dry most firmly pressed between bookpages and can dry.