The Autumn Palette: The Science Behind Fall Leaves
Each Autumn, leaves change from green to fiery reds, warm oranges, and golden yellows. But why does this happen? It's actually due to a process called photosynthesis. During Spring and Summer, trees use sunlight to make food, a process known as photosynthesis. The green color you see in leaves is due to a substance called chlorophyll, which is essential for photosynthesis. But as Fall approaches and the days get shorter, the trees start to prepare for winter. They slow down their food production and stop making chlorophyll. With less green color, the yellow and orange pigments, which were always in the leaves but hidden by the green, start to shine through. Sometimes, the leaves even turn red or purple. This happens when the tree sends sugar to the leaves, and the sugar gets trapped, creating bright red pigments. Imagine a forest in Fall with trees full of leaves like colorful flames against a clear blue sky. From bright yellow to deep maroon, the colors of Fall provide a beautiful farewell to Summer.
Question 1
What is the process called when trees use sunlight to make food?
Transpiration
Respiration
Digestion
Photosynthesis
Absorption
Question 2
Why do leaves change color in the fall?
Because of the cold weather
Because of rain
Because trees stop making chlorophyll
Because of the wind
Because of the heat
Question 3
What is the substance that gives leaves their green color?
Carotenoids
Anthocyanins
Chlorophyll
Xanthophylls
Cellulose
Question 4
What causes the red or purple color in leaves during fall?
The tree sends sugar to the leaves
The tree absorbs water from the ground
The tree absorbs more sunlight
The tree produces more chlorophyll
The tree loses its leaves
Question 5
True or False: The yellow and orange pigments are always present in the leaves, but are just hidden by the green color in spring and summer.
True
False
Can be both
Depends on the type of tree
Depends on the season
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