explain the human eye
Answers
The human eye is a paired sense organ that reacts to light and allows vision. Rod and cone cells in the retina are photoreceptive cells which are able to detect visible light and convey this information to the brain. ... The eye is part of the sensory nervous system.
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Human eye is the most important organ. It is used to see the beautiful nature and the natural phenomena. The human eye works on the refraction of light through a natural convex lens made of transparent living material and enable us to see things around us.
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Cornea, Iris, Pupil, Ciliary muscles, eye lens, retina and optic nerves.
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It is transparent part of eye and allow the light to enter in the eyes, it is the outermost part of the eye.
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It is a circular diaphragm having a hole in it's centre. This hole is called . The circular diapragm has muscles and coloured pigments. The colour of an eye depends on the colour of these pigments. The function of iris is to control the amount of light entering the eye through the pupil. The pupil becomes small when bright light falls on the eye but it becomes wide when there is dim light.
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These muscles hold the eye lens in position. It controls the focal length of eye lens. When these muscles contracts the focal length of the lens increases when they expands they exerts pressure on the lens and decreases focal length.
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It acts as a screen to obtain the image of object. It contains number of cells in the form of rods and cones which are sensitive towards light. These cells convert light energy to into nerve impulses or signals.
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Optic nerve is found by the nerve fibres coming from the retina. It transfers nerve impulses to the brain.
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When will look towards an object light from the object enters the pupil of the eye and falls on the eyelens. The lens forms a real and inverted image on the retina of the eye. The retina of the eye contains special cells in the shape of rods and cones. These cells convert light energy into electrical signals. These electrical signals carried to the brain through the optic nerves.