Why Do Leaves Change Color In The Fall.

1. Why Do Leaves Change Color In The Fall. Lesson for second grade students Mandy Hakkarainen mhakkara@nmu.edu

2. Important words to know • Carbon Dioxide-gas from the air • Glucose- a kind of sugar used for energy and the building blocks for growing • Photosynthesis- the process by which plants make food. Simple way to remember this is “putting together with light” • Chlorophyll-help the photosynthesis process and this chemical gives leaves their green color

3. Diagram of what is going on in the leaves • Water from the ground travels through the roots up to the leaves • Carbon dioxide gas come from the air • Sunlight hits the leaves and turns the water and carbon dioxide into glucose • This process is know as Photosynthesis

4. How Does the Tree Know When To Change Color? • Summer ends and Fall comes, the days get shorter and shorter. This is how the tree “knows” to begin getting ready for winter. • During the winter months there is not enough light or water for photosynthesis. • The tree will rest during the winter and live off the food it has stored during the summer.

5. What Makes the Different Colors in the Leaves? • The green chlorophyll disappears from the leaves because photosynthesis is no longer taking place. • The yellow and orange that will appear in the leaves is color that has always been there, but these colors were covered up will chlorophyll in the summer.

6. What Makes the Different Colors in the Leaves? • Bright reds and Purples are made mostly in the fall. • In Maple trees the glucose is trapped in the leaves after photosynthesis stops. • Sunlight and cool nights turn the glucose into a red color. • Brown color in Oaks is made from wastes left in the leaves.

7. A Word Scramble How many of these words can you unscramble? trawe afle rnege ernago mutanu loscuge gnlituhs holopryclh

8. A Fun Fact About Fall Leaves • What do fall leaves and ripening bananas have in common? • The green color in unripe bananas comes from chlorophyll; the same pigment that gives green leaves their color. As bananas ripen, the chlorophyll breaks down and disappears, revealing the yellow color, which has been there all along.

9. Continue Fun Fact • The yellows and oranges of fall leaves are also revealed as their chlorophyll breaks down. Of course, other changes also occur as bananas ripen: the starches change to sugar and the flesh softens as pectin (a carbohydrate) breaks down.

10. Here are a few projects in a PDF document that are great to use in a classroom. PDF document ANSWERS TO WORD SCRAMBLE water leaf green orange autumn glucose sunlight chlorophyll For the teacher