The purpose of the human eyes is to see. Perception or depth, color differentiation, and vision are made able by the cone and rod cells found in the retina part of the organ. Research has indicated that human eyes are capable of seeing ten million different colors. When in need of good eye care, San Antonio is a recommendable location to make a visit. San Antonio eye specialists have the right experience and qualification to handle any disease that affects eyes.
The shape of eyes is not a perfect sphere. They are made up of two pieces joined together. Of the two parts, the frontal part is called the cornea. Cornea is curved in shape, transparent in color, and is joined to the bigger peripheral part called sclera. The typical radius of the cornea is 8 mm while sclera has a radius of 12 mm. The connection of sclera and cornea is done by the limbus ring while the iris surrounds the pupil.
The iris has two kinds of muscles called the sphincter and dilator muscles, which adjust the size of the pupil. Light from outside enters the eyes through the cornea. The retina is responsible for converting light falling on its light-sensitive cells into electrical signals which are transported to the brain for processing. The electrical signals are carried by the optic nerves. Ophthalmoscope is the device used to see inside the eyes.
In adults, eyes differ in size from one another by either one or two millimeter. This is true for all kinds of ethnicities in the world. There is also variance in sagittal, horizontal, and vertical measurements without any observable variation based on age group or gender. Rapid growth occurs in eyes from birth to age 3. By age thirteen, the eyes will have achieved their full size.
Eyes are made up of three coats, which enclose three transparent structures. The outermost coat is referred to as the fibrous tunic. The fibrous tunic comprises of the sclera and cornea. The middle layer is called the uvea or vascular tunic. Uvea is comprised of the iris, ciliary body, and choroid. The retina forms the innermost layer. An ophthalmoscope can be used to see all the named layers.
Inside those coats are aqueous humour, the vitreous body, and flexible lens. Aqueous humour occurs in the posterior and anterior chamber. The anterior chamber is placed between iris and cornea whereas the space between iris and lens holds the posterior chamber. Suspension of the lens is done by suspensory ligament. Vitreous body is placed behind lens.
Six different muscles in the eyes are responsible for movement. The muscles include medial rectus, superior rectus, inferior oblique, lateral rectus, medial rectus, and superior oblique. The muscles exert a torque on the globe resulting in pure rotation. The torque also causes translation of around a millimeter.
Different causes cause different diseases and conditions in the eyes. The causes may be in the form of aging, disease, or disorders. Problems of the eyes caused by aging result because of physiological changes caused by the aging process. Newborns may also suffer from diseases since birth. Ophthalmologists, opticians, and optometrists are some of the medical professionals who specialize in the eye.
The shape of eyes is not a perfect sphere. They are made up of two pieces joined together. Of the two parts, the frontal part is called the cornea. Cornea is curved in shape, transparent in color, and is joined to the bigger peripheral part called sclera. The typical radius of the cornea is 8 mm while sclera has a radius of 12 mm. The connection of sclera and cornea is done by the limbus ring while the iris surrounds the pupil.
The iris has two kinds of muscles called the sphincter and dilator muscles, which adjust the size of the pupil. Light from outside enters the eyes through the cornea. The retina is responsible for converting light falling on its light-sensitive cells into electrical signals which are transported to the brain for processing. The electrical signals are carried by the optic nerves. Ophthalmoscope is the device used to see inside the eyes.
In adults, eyes differ in size from one another by either one or two millimeter. This is true for all kinds of ethnicities in the world. There is also variance in sagittal, horizontal, and vertical measurements without any observable variation based on age group or gender. Rapid growth occurs in eyes from birth to age 3. By age thirteen, the eyes will have achieved their full size.
Eyes are made up of three coats, which enclose three transparent structures. The outermost coat is referred to as the fibrous tunic. The fibrous tunic comprises of the sclera and cornea. The middle layer is called the uvea or vascular tunic. Uvea is comprised of the iris, ciliary body, and choroid. The retina forms the innermost layer. An ophthalmoscope can be used to see all the named layers.
Inside those coats are aqueous humour, the vitreous body, and flexible lens. Aqueous humour occurs in the posterior and anterior chamber. The anterior chamber is placed between iris and cornea whereas the space between iris and lens holds the posterior chamber. Suspension of the lens is done by suspensory ligament. Vitreous body is placed behind lens.
Six different muscles in the eyes are responsible for movement. The muscles include medial rectus, superior rectus, inferior oblique, lateral rectus, medial rectus, and superior oblique. The muscles exert a torque on the globe resulting in pure rotation. The torque also causes translation of around a millimeter.
Different causes cause different diseases and conditions in the eyes. The causes may be in the form of aging, disease, or disorders. Problems of the eyes caused by aging result because of physiological changes caused by the aging process. Newborns may also suffer from diseases since birth. Ophthalmologists, opticians, and optometrists are some of the medical professionals who specialize in the eye.
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