photoreceptor
Quick Summary
Photoreceptors are specialized cells in the retina of the eye that detect light, enabling vision. In vertebrates, there are two main types: rods and cones.123
Rods are more numerous and highly sensitive to low light levels, responsible for detecting shapes and brightness but not color or fine detail. Cones are less sensitive to light and are concentrated in the central retina, responsible for color vision and sharp detail.23
When light strikes these cells, it triggers chemical changes that are converted into electrical signals. These signals are then relayed through other neurons in the retina to the optic nerve, which transmits them to the brain for processing.41
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sensesLight senses…vision, or photoreception, relies on photoreceptors that contain a special light-detecting molecule known as rhodopsin. Rhodopsin detects electromagnetic radiation—light with wavelengths in the range 400–700 nanometres (1 nm = 10−9m). There are some animals that can detect infrared radiation (wavelengths greater than 700 nm); for example, some
Read More…vision, or photoreception, relies on photoreceptors that contain a special light-detecting molecule known as rhodopsin. Rhodopsin detects electromagnetic radiation—light with wavelengths in the range 400–700 nanometres (1 nm = 10−9m). There are some animals that can detect infrared radiation (wavelengths greater than 700 nm); for example, some
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photoreceptionStructure and function of photoreceptorsPhotoreceptors are the cells in the retina that respond to light. Their distinguishing feature is the presence of large amounts of tightly packed membrane that contains the photopigment rhodopsin or a related molecule. The tight packing is needed to achieve a
Read MorePhotoreceptors are the cells in the retina that respond to light. Their distinguishing feature is the presence of large amounts of tightly packed membrane that contains the photopigment rhodopsin or a related molecule. The tight packing is needed to achieve a
Read More