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The visual system is the physiological basis of visual perception (the ability to detect and process light).The system detects, transduces and interprets information concerning light within the visible range to construct an image and build a mental model of the surrounding environment.
In order, along the optic axis, the optical components consist of a first lens (the cornea—the clear part of the eye) that accounts for most of the optical power of the eye and accomplishes most of the focusing of light from the outside world; then an aperture (the pupil) in a diaphragm (the iris—the coloured part of the eye) that controls ...
The sensory nervous system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons (including the sensory receptor cells), neural pathways , and parts of the brain involved in sensory perception and interoception .
Taste is the sensation produced when a substance in the mouth reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with smell ( olfaction ) and trigeminal nerve stimulation (registering texture, pain, and temperature), determines flavors of food or other substances.
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth. The human eye can distinguish about 10 million colors. [3]
Visual phototransduction is the sensory transduction process of the visual system by which light is detected by photoreceptor cells (rods and cones) in the vertebrate retina.A photon is absorbed by a retinal chromophore (each bound to an opsin), which initiates a signal cascade through several intermediate cells, then through the retinal ganglion cells (RGCs) comprising the optic nerve.
The rate of firing of the ganglion cells is increased when it is signaled by one cone and decreased (inhibited) when it is signaled by the other cone. The first color in the name of the ganglion cell is the color that excites it and the second is the color that inhibits it. i.e.:
The globe of the eye, or bulbus oculi, is the frontmost sensory organ of the human ocular system, going from the cornea at the front, to the anterior part of the optic nerve at the back. More simply, the eyeball itself, as well as the ganglion cells in the retina that eventually transmit visual signals through the optic nerve. [1]