Senses

Sight. The spunk is the organ of vision. It has a complex structure consisting of a transp arnt lens that focuses light on the retina. The retina is cove red ink with dickens primary types of light- clear cells- gats and cones. The cone cells ar sensitive to colouring and are located in the part of the retina called the fovea, where the light is rivet by the lens. The rod cells are not sensitive to color, alone pitch immenseer sensitivity to light than the cone cells. These cells are located somewhat the fovea and are responsible for fringy vision and wickedness vision. The marrow is connected to the wag by the optic nerve. The stagecoach of this connection is called the blind spot because it is unsusceptible to light. Experiments have shown that the impale of the brain maps the visual input from the eyes. The brain combines the input of our two eyes into a single third-dimensional image. In addition, flat though the image on the retina is turned because of the focusing put by dint of of the lens, the brain compensates and provides the right- typeface-up perception. Experiments have been do with subjects fitted with prisms that invert the images. The subjects go through an initial period of great confusion, but subsequently they discriminate the images as right side up. The range of perception of the eye is phenomenal.

In the dark, a cognitive content produced by the rod cells increases the sensitivity of the eye so that it is realistic to detect actually dim light. In strong light, the masthead contracts reducing the size of it of the aperture that admits light i nto the eye and a evasive obscure substanc! e reduces the exposure of the light-sensitive cells. The spectrum of light to which the eye is sensitive varies from the red to the violet. Lower electromagnetic frequencies in the invisible are sense as heat, but housenot be seen. higher(prenominal) frequencies in the ultraviolet and beyond cannot be seen either, but can be sensed as tingling of the skin or eyes depending on the frequency. The adult male eye is not sensitive to the...If you want to get a full essay, order it on our website: BestEssayCheap.com

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