The human eye is a 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. Eyes signal information which is used by the brain to elicit the perception of color, shape, depth, movement, and other features. The eye is part of the sensory nervous system.
The eyes sit in bony cavities called the orbits, in the skull. The front visible part of the eye is made up of the whitish sclera, a colored iris, and the pupil. A thin layer called the conjunctiva sits on top of this. The front part is also called the anterior segment of the eye.
The eye is made up of three coats, or layers, enclosing various anatomical structures. The outermost layer, known as the fibrous tunic, is composed of the cornea and sclera, which provide shape to the eye and support the deeper structures. The middle layer, known as the vascular tunic or uvea, consists of the choroid, ciliary body, pigmented epithelium and iris. The innermost is the retina, which gets its oxygenation from the blood vessels of the choroid (posteriorly) as well as the retinal vessels (anteriorly).
The spaces of the eye are filled with the aqueous humour anteriorly, between the cornea and lens, and the vitreous body, a jelly-like substance, behind the lens, filling the entire posterior cavity. The aqueous humour is a clear watery fluid that is contained in two areas: the anterior chamber between the cornea and the iris, and the posterior chamber between the iris and the lens. The lens is suspended to the ciliary body by the suspensory ligament (Zonule of Zinn), made up of hundreds of fine transparent fibers which transmit muscular forces to change the shape of the lens for accommodation (focusing). The vitreous body is a clear substance composed of water and proteins, which give it a jelly-like and sticky composition.
Each eye has six extraocular muscles that control its movements: the lateral rectus, the medial rectus, the inferior rectus, the superior rectus, the inferior oblique, and the superior oblique.
#医学生Medic[超话]##medicaltalks#
The eyes sit in bony cavities called the orbits, in the skull. The front visible part of the eye is made up of the whitish sclera, a colored iris, and the pupil. A thin layer called the conjunctiva sits on top of this. The front part is also called the anterior segment of the eye.
The eye is made up of three coats, or layers, enclosing various anatomical structures. The outermost layer, known as the fibrous tunic, is composed of the cornea and sclera, which provide shape to the eye and support the deeper structures. The middle layer, known as the vascular tunic or uvea, consists of the choroid, ciliary body, pigmented epithelium and iris. The innermost is the retina, which gets its oxygenation from the blood vessels of the choroid (posteriorly) as well as the retinal vessels (anteriorly).
The spaces of the eye are filled with the aqueous humour anteriorly, between the cornea and lens, and the vitreous body, a jelly-like substance, behind the lens, filling the entire posterior cavity. The aqueous humour is a clear watery fluid that is contained in two areas: the anterior chamber between the cornea and the iris, and the posterior chamber between the iris and the lens. The lens is suspended to the ciliary body by the suspensory ligament (Zonule of Zinn), made up of hundreds of fine transparent fibers which transmit muscular forces to change the shape of the lens for accommodation (focusing). The vitreous body is a clear substance composed of water and proteins, which give it a jelly-like and sticky composition.
Each eye has six extraocular muscles that control its movements: the lateral rectus, the medial rectus, the inferior rectus, the superior rectus, the inferior oblique, and the superior oblique.
#医学生Medic[超话]##medicaltalks#
想必你见过那些身材俊朗的斑点狗吧！但是你见过那些健硕优美的斑点马吗？[亲亲][亲亲]
它们来自北美洲的【阿巴鲁沙马Appaloosa Horse】[奥特曼][奥特曼]
关于这种体色斑驳马种的最初起源众说纷纭，一般说来是一种欧洲马经过基因突变引起，后来这些斑点色流入美洲，由著名的印第安「内兹珀斯人Nez Perce」选育驯养，最终稳定了其斑驳基因！并且在斑纹背后更是选育出了其极好的耐力，和无畏的性格，并且在日后诸多南征北战中大显异彩！[酷][酷]
然而，18世纪的阿巴鲁沙马体型大小差异很大，为了形成更稳定的标准体格，阿巴鲁沙马又和阿拉伯马进行混血，形成了如今的“最终形态”！[憧憬][憧憬]
不过非常有意思的是，不管怎么混血，有几样有趣的特征却一直保留在它们体内，比如它们的蹄子是天然带白色纹路的，它们的巩膜是白色的，分外英俊！[打call][打call]
#灰照猫的魔怪世界[超话]#
它们来自北美洲的【阿巴鲁沙马Appaloosa Horse】[奥特曼][奥特曼]
关于这种体色斑驳马种的最初起源众说纷纭，一般说来是一种欧洲马经过基因突变引起，后来这些斑点色流入美洲，由著名的印第安「内兹珀斯人Nez Perce」选育驯养，最终稳定了其斑驳基因！并且在斑纹背后更是选育出了其极好的耐力，和无畏的性格，并且在日后诸多南征北战中大显异彩！[酷][酷]
然而，18世纪的阿巴鲁沙马体型大小差异很大，为了形成更稳定的标准体格，阿巴鲁沙马又和阿拉伯马进行混血，形成了如今的“最终形态”！[憧憬][憧憬]
不过非常有意思的是，不管怎么混血，有几样有趣的特征却一直保留在它们体内，比如它们的蹄子是天然带白色纹路的，它们的巩膜是白色的，分外英俊！[打call][打call]
#灰照猫的魔怪世界[超话]#
The human eye is a 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. Eyes signal information which is used by the brain to elicit the perception of color, shape, depth, movement, and other features. The eye is part of the sensory nervous system.
#医学生Medic[超话]##medicaltalks#
#医学生Medic[超话]##medicaltalks#
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