A specialized type of nerve cell that is sensitive to light and that sends signals to other neurons by a change in its membrane potential when it absorbs photons. This information is subsequently used by the brain to form a representation of the visual world. In the retina of the vertebrate eye are found two types of photoreceptor cells: rod cells and cone cells.
In plants, photoreceptors are light-detectors containing the blue-green pigment phytochrome. They are involved in many plant processes, such as seed germination, flowering, and leaf fall.
Related categories• CELL BIOLOGY
• ANATOMY AND PHYSIOLOGY
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