Human eyes review image diversity human eye eye

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Human Eyes Review - Image Diversity: human eye eye anatomy 4. What are the main structures of the human eye? The main structures of the human eye are the cornea, the iris, the pupil, the ciliary muscles, the crystalline lens and the retina (the space between the crystalline lens and the retina within the eyeball is filled with the vitreous humor).
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5. What is the function of the iris and of the pupil? The iris works like the diaphragm of a camera, since it has muscles that contract or relax, varying the diameter of the pupil. When the intensity of light increases, the parasympathetic nervous system commands the pupil to contract; and when there is a shortage of light, the sympathetic nervous system stimulates the dilation of the pupils. These movements depend upon the muscles of the iris. 6. Photoreceptor cells are cells that sense light. In which part of the human visual system are they located? How do these cells work? Photoreceptor cells form the retina, a lamina that covers the internal posterior region of the eyeball. The photosensitive cells of the retina are divided into two types: cone cells and rod cells. These cells contain pigments that sense specific light wave ranges (frequencies) and trigger action potentials transmitted by the optic nerves to the visual area of the brain. Hyman Eyes Review - Image Diversity: retina histology cone cells rod cells 7. Since visual images are projected in an inverted manner on the retina why don't we see things upside down?
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Since the crystalline lens is a convex spherical lens, it forms inverted images on the retina (every converging lens forms inverted images). The inverted information is transmitted via the optic nerves to the occipital cerebral cortex, which contains the visual area of the brain. In the brain. the interpretation of the
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