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Photosynthesis is the process by which green plants use light energy to convert carbon dioxide and water into glucose (a sugar) and oxygen.
Chlorophyll is a green pigment found in the chloroplasts of plant cells. It is absolutely essential for photosynthesis.
Chlorophyll works by absorbing light energy, primarily in the blue and red wavelengths of the visible spectrum. This absorbed light energy then drives the chemical reactions of photosynthesis.
Without chlorophyll, plants cannot effectively absorb the light energy needed to power photosynthesis. This means they cannot produce glucose, which is their primary source of energy and building material.
Different pigments absorb different wavelengths of light. Chlorophyll a and chlorophyll b are the main types of chlorophyll in plants. They absorb light most efficiently in the blue and red regions of the electromagnetic spectrum, reflecting green light, which is why plants appear green to our eyes.
| Pigment | Wavelength Absorbed | Colour Reflected |
|---|---|---|
| Chlorophyll a | Blue and Red | Green |
| Chlorophyll b | Blue and Red | Green |
The absorbed light energy is used in the light-dependent reactions of photosynthesis, which occur in the thylakoid membranes within the chloroplasts. These reactions convert light energy into chemical energy in the form of ATP and NADPH.