What are 2 facts about the blind spot in the human eye?
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It is blind\nIt is a spot.
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Hyperopia, also known as hypermetropia or colloquially as farsightedness or longsightedness, is a defect of vision caused by an imperfection in the eye (often when the eyeball is too short or when the lens cannot become round enough), causing inability to focus on near objects, and in extreme cases causing a sufferer to be unable to focus on objects at any distance. As an object moves towards the eye, the eye must increase its power to keep the image on the retina. If the power of the cornea and lens is insufficient, as in hypermetropia, the image will appear blurred.
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it depends on the shape of your eye
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The cornea (thats the very front  part of the eye which is clear- its clear because of no blood vessels)..it derives its nutrition from a fluid behind it called the aqueous humour...
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eye = light \nears = sound\nnose = chemical
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Red.  It is of relatively low frequency in relation to other discernible colors, and has a wavelenght between 630 and 760 nm.  That is the only way you can expalain a color to a blind person if they were blind from birth.
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I am an MD. This is a very interesting question. The resolution of the naked eye among people with the finest vision is about 1 arc minute. Star discs are far, far, smaller than this, so how can the eye see something that is that small? The answer is that a typical star image, though exceedingly small, is nevertheless very bright when compared to the night sky. The star image will appear as a diffraction (Airy) disk on the surface of your retina that is about one arc minute in diameter that is too bright to be ignored. Your retinal cells process the incoming light and send the signal to your brain, and what you perceive is a tiny bright speck. This is perhaps equivalent to your digital camera showing a star image consisting of a single pixel being illuminated. I hope this helps.
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I'm so not good at science, but isn't the pupil a hole? And the iris is a muscle surrounding it that contracts and expands upon exposure to light. If indeed it is a hole......perhaps this is why it is dark. *shrugs*
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Many eye diseases can lead to blindness-glaucoma being the most widely known.
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The things that blind people read off of.
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C. At the Fovea\nThe fovea is the centermost point in the macula, and responsible for our central, sharpest vision known as MACULA LUTEA
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1) its optical centre\n2) 1/2 cm\n3)converges, diverges\n4)perpendicular incidence of light\n5)ciliary muscles
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Basically, light passes through the front of the eye, the pupil, and the crystalline lens.  It hits the retina (the back of the eye), which has special cells that transform the light energy into a signal that the brain can understand.  The brain then interprets the image.  Of course, there are many other things that come into play, like how the eyes work together and how strong the eyes are.
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http://en.wikipedia.org/wiki/Eyesight
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Why cant u start with eyes and its functioning,what are the lipids responsible for sight?Which is going to message the picture we have saw?how we can feel that picture in our brain?So that ur research goes to search a way to provide sight for blind or rectifies sight?
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The colored part of your eye is the iris, and all it does is control the amount of light that passes into the eye by varying the size of your pupil.  Light passes through that opening to the retina at the back of the eye where the rods and cones convert the lightwaves into the nerve signals that your brain recognizes as objects, colors, etc.
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In the physical body the eye views objects upside down. It sends the image of what it observes to the brain which interprets the image and makes it appear right side-up to us.\n\nBut the human body has another physical eye whose function has long been recognized by humanity. It is called the 'Third Eye' which in reality is the Pineal Gland. It is long thought to have mystical powers. Many consider it the Spiritual Third Eye, our Inner Vision. \n\nIt is located in the geometric center of the brain. This correlates to the location of the Great Pyramid in the center of the physical planet.\n\nThe Pineal Gland is about the size of a pea, and is in the center of the brain in a tiny cave behind and above the pituitary gland which lies a little behind the root of the nose. It is located directly behind the eyes, attached to the third ventricle.\n\nThe true function of this mysterious gland has long been contemplated by philosophers and Spiritual Adepts. Ancient Greeks believed the pineal gland to be our connection to the Realms of Thought. Descartes called it the Seat of the Soul. This gland is activated by Light, and it controls the various biorhythms of the body. It works in harmony with the hypothalamus gland which directs the body's thirst, hunger, sexual desire and the biological clock that determines our aging process.\n\nWhen the pineal gland awakens one feels a pressure at the base of the brain. This pressure will often be experienced when connecting to higher frequency. A head injury can also activate the Third Eye - Pineal Gland.\n\nWhile the physiological function of the pineal gland has been unknown until recent times, mystical traditions and esoteric schools have long known this area in the middle of the brain to be the connecting link between the physical and spiritual worlds. Considered the most powerful and highest source of ethereal energy available to humans, the pineal gland has always been important in initiating supernatural powers. Development of psychic talents has been closely associated with this organ of higher vision.\n\nThere is a pathway from the retinas to the hypothalamus called the retinohypothalamic tract. It brings information about light and dark cycles to a region of the hypothalamus called the suprachiasmatic nucleus(SCN). From the SCN, nerve impulses travel via the pineal nerve (sympathetic nervous system) to the pineal gland. These impulses inhibit the production of melatonin. When these impulses stop (at night, when light no longer stimulates the hypothalamus), pineal inhibition ceases and melatonin is released. The pineal gland is therefore a photosensitive organ and an important timekeeper for the human body.\n\nRetinal research done with hamsters demonstrates another center for melatonin production. Located in the retina, this center implies that the eyes have their own built in circadian timepiece. This retinal system is distinct from the brains body clock in the suprachiasmatic nucleus (SCN). Biologists found that they could throw the retinal rhythms out of sync with other circadian cycles. They also found that they could set and reset the retinal clock even when the SCN was destroyed.\n\nThe retinal clock produces (stimulates the production of?) melatonin. Researchers are now looking for the exact location (s) of this clock in the human eye (and expect to find it). No one yet knows what the separate clock is for or how it relates to the SCN. \n\nIn some lower vertebrates the Epiphysis Cerebri - Pineal Gland - has a well-developed eye-like structure; in others though not organized as an eye, if functions as a light receptor. In lower vertebrates, the pineal gland has an eye like structure and it functions as a light receptor and is considered by some to be the evolutionary forerunner of the modern eye.\n\nThe gland weighs little more than 0.1 gram. The gland is large in children and begins to shrink with the onset of puberty. It appears to play a major role in sexual developmen