Nerve06/eyes and ears/introduction of eye anatomy
The upper half is the view from the front, and the lower half is the horizontal cross section.
The cornea is in the center of the very front plane. It is transparent, letting light into the eyes. (In the lower half, the part where the light-dark blue of the back can be seen is transparent).
The so-called 'whites' of the eye is the conjunctiva. As with the cornea, it is in the very fron plane, but is not transparent, but white, not allowing lights through.
The colored area of the eye is the iris (3). It is doughnut-shaped, and with the shape-changing, the amount of light entering the eye is adjusted. The whole part of the doughnut is the pupil (4). It is the name of a whole and there is nothing there. It is the entry gate for the light into the eye. Light passing through the pupil travels through the lens (5). It can bend the light and plays a role in focusing as do the lens in cameras. This is also transparent. Light, then passes through the vitreous body (6). Naturally, it is transparent. It locates at the center of the eye, forming its ball-shape. Since it does not bend the light, it is not involved in focusing.
The retina (7 in green), which is just in front of the back wall of the eye, is the receptor of the light, generating action potential.
The generated electrical signal (action potential) travels through the nerve fibers (thick black line) in front (inner side) of the retina. The fibers are then bundles into one nerve.
The sensory (afferent) peripheral nerve thus formed, the optic nerve (8), travels backwards through the retina, delivers the electric signals (action potential) to the brain.
Challenge Quiz
図の*印は 角膜.結膜. 虹彩. 瞳孔. 水晶体. ガラス体. 網膜. 視神経 である。
図の*印は 角膜 結膜 虹彩 瞳孔 水晶体 ガラス体 網膜 視神経 である。
眼球内にあってレンズとして作用している部位は、 胸膜 結膜 角膜 脈絡膜 網膜 毛様体 虹彩 水晶体 ガラス体 である。
眼球内にあって光量調節を担っている部位は、 胸膜 結膜 角膜 脈絡膜 網膜 毛様体 虹彩 水晶体 ガラス体 である。