Two major types of photosynthetic pigments are chlorophyll and carotenoids.
Chlorophyll: The Primary Pigment
Chlorophyll is the primary pigment responsible for capturing light energy during photosynthesis. Different types of chlorophyll exist, with chlorophyll a and chlorophyll b being the most common in plants. Chlorophyll a directly participates in the light-dependent reactions of photosynthesis, while chlorophyll b acts as an accessory pigment, absorbing light energy and transferring it to chlorophyll a.
- Key function: Absorbs primarily blue and red light, reflecting green light (which is why plants appear green).
- Location: Found within chloroplasts, specifically in the thylakoid membranes.
Carotenoids: Accessory Pigments
Carotenoids are accessory pigments that broaden the range of light absorbed by plants. They absorb light in the blue-green region of the spectrum. Beyond their role in light absorption, carotenoids also protect chlorophyll from damage caused by excessive light energy.
- Key function: Absorb light energy and transfer it to chlorophyll a, protecting chlorophyll from photooxidation.
- Examples: Beta-carotene (orange) and various xanthophylls (yellow).
- Location: Found in chloroplasts, alongside chlorophylls.
The major groups of photosynthetic pigments are: Chlorophyll and Carotenoids.
