Here's why:
* Chlorophyll is a pigment: It absorbs specific wavelengths of light, primarily red and blue light, and reflects green light, which is why plants appear green.
* Light energy capture: When chlorophyll absorbs light energy, it becomes excited and its electrons move to higher energy levels.
* Energy transfer: This excited state is unstable, so the energy is passed along to other molecules in the chloroplasts, ultimately being used to power the chemical reactions of photosynthesis.
So, while chloroplasts are the organelles where photosynthesis takes place, it's the chlorophyll within them that actually captures the light energy needed to make sugars from carbon dioxide and water.
