Final answer:
Chloroplasts are green because of the pigment chlorophyll, which absorbs red and blue light and reflects green light.
Step-by-step explanation:
Chloroplasts are green because they contain a pigment called chlorophyll, which is responsible for absorbing light for photosynthesis. Chlorophyll mainly absorbs red and blue light, but reflects green light, giving chloroplasts their green color. This is due to the fact that chlorophyll molecules absorb light in the red and blue regions of the electromagnetic spectrum, while reflecting or transmitting light in the green region.
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