The physical signs of fall begin when the leaves change color and start to fall from the trees. This transformation is triggered by shorter daylight hours and cooler temperatures.
The process of changing leaf colors is often referred to as "fall foliage." But what exactly happens scientifically to cause this change?
The green color in leaves comes from a pigment called chlorophyll, which is produced during photosynthesis. Photosynthesis is the process by which plants convert light energy from the sun into chemical energy, producing oxygen in the process. However, when the supply of water to the leaves is cut off, photosynthesis slows and eventually stops.
As a result, chlorophyll production halts, and the green color fades or decomposition begins. This allows other pigments in the leaf, such as carotenoids (which produce yellow and orange hues) and anthocyanins (which create red and purple shades), to become more visible.
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This beautiful transformation gives us the vibrant colors of fall that we all love!
