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 rosy with dickens int celestial poleuctory types of light- clear cells-rods and cones. The cone cells are 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 amaze immenseer sensitivity to light than the cone cells. These cells are located nearly the fovea and are responsible for fringy vision and shadow vision. The nerve centre is connected to the wag by the optic nerve. The compass point of this connection is called the blind spot because it is unsusceptible to light. Experiments have shown that the can of the brain maps the visual input from the eyes. The brain combines the input of our both eyes into a single third-dimensional image. In addition, blush though the image on the retina is turn ed because of the focusing bodily process 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 done an initial period of great confusion, but subsequently they recognize 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 genuinely dim light. In strong light, the masthead contracts reducing the sizing of the aperture that admits light into the eye and a evasive obscure center reduces the exposu! re 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 perceived 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 kind-hearted 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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