Final answer:
Each type of pigment responds to a different wavelength of light due to the presence of different types of opsins. In humans, this is exemplified by the photoreceptors in the eye known as cones, which allow for color vision. Plants have chlorophyll and carotenoid pigments with unique absorption spectra contributing to the absorption of light for photosynthesis.
Step-by-step explanation:
Each type of pigment responds to a different wavelength of light. This is because each type contains a different type of opsin. In the human eye, there are photoreceptor cells known as cones, which come in three types: S cones, M cones, and L cones. These cones contain opsins that are responsive to specific wavelengths of light, resulting in color vision. For example, S cones are most responsive to short wavelengths (420 nm), corresponding to blue light. M cones respond to medium wavelengths (530 nm), associated with green light, and L cones are sensitive to long wavelengths (560 nm), corresponding to red light.
Plants also have different types of pigments like chlorophyll a, chlorophyll b, and carotenoids such as ß-carotene, each with their own absorption spectrum. Chlorophyll a absorbs blue and red light, reflecting green, which is why plants appear green. Carotenoids absorb blue light and reflect longer wavelengths like yellow, red, and orange. This distinct pattern of absorption by pigments enables the capture of light for processes such as photosynthesis.