2. Middle School Science Mrs. Figoten Mrs. Figoten

3. DO LEAVES ON TREES IN ALL BIOMES CHANGE COLOR? Leaves change color seasonally only in deciduous forests.

4.  Warm summers & cold winters  50+ cm precipitation/yr  Trees shed leaves yearly

5. AUTUMN LEAF CHANGES Earth’s tilt changes in Northern Hemisphere Less daylight, cooler temperatures What signals leaves to change color in autumn?

6. What causes leaf color? 3 pigments in each leaf- the amount in each leaf varies Chlorophyll Carotene Carotene Anthocyanin Anthocyanin AUTUMN LEAF CHANGES

7. Leaf appears green Present in leaf membrane Needs sunlight in order to make food for tree through photosynthesis

8. Leaf appears yellow Leaf appears yellow Remains in leaf membrane as chlorophyll disappears Remains in leaf membrane as chlorophyll disappears Helps with photosynthesis Helps with photosynthesis Birch & Hickory leaves Birch & Hickory leaves have lots of carotene have lots of carotene

9. Leaf appears red/purple Leaf appears red/purple Present in cell sap Present in cell sap Reacts with sugar from photosynthesis Reacts with sugar from photosynthesis In some trees, sugar in leaves increases in autumn In some trees, sugar in leaves increases in autumn Red Maple, Red Oak & Sumac leaves have lots of anthocyanin Red Maple, Red Oak & Sumac leaves have lots of anthocyanin

14. WHAT DO PLANTS NEED FOR PHOTOSYNTHESIS?

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18. DOES ANYTHING ELSE MAKE ITS OWN FOOD USING PHOTOSYNTHESIS?