Question

Read this PBS article (Links to an external site.) discussing why leaves change colors. After reading this article and using other resources as needed, prepare and post the following:

1. A brief summary of why leaves change colors in the fall, relating specifically to solar energy and photosynthesis.
2. A more detailed discussion of 1 pigment related to fall colors. Be sure to include the pigment's name, chemical formula, and what wavelengths of solar energy it absorbs/reflects.
3. Your references.

Answer 1

The change in colour of leaves usually happens before leaf fall because the chlorophyll pigment break down due to change in outer environment conditions like temperature, length of day light, etc. So, green colour disappears and energy is saved which is required for chlorophyll synthesis. Leaves also have other pigments llike carotenoids whihc give yellow to orange colour. Anthocyanins are also present which gives red, pink to purple colours. In chlorophyll absence these pigments show their effect/ color.

Pigment	Chemical formula	wavelength (Absorb)
Chlorophyll a	C55H72O5N4Mg	435, 670, 680
Chlorophyll b	C55H70O6N4Mg	453, 480, 650
Alpha cartene	C40H56	450, 470