Part Ⅳ Sensory Organs 感 觉 器

The Sensory Organs Sensory organs include receptors感受器 accessory organs辅助装置. The receptors may be divided into three kinds: exteroceptors 外感受器:分布在皮肤、鼻腔和口腔粘膜、视器和听器等处， receive stimuli such as touch, temperature, pain, light and sound from the external environment interoceptors 内感受器:分布于内脏和心血管等处pick up information about internal environment proprioceptors 本体感受器:分布在肌肉、肌腱、关节、韧带和内耳平衡器等处receive stimuli from muscles, tendons, joints and ligaments

chapter 1 The Visual Organ 视器 The Visual Organ consist of eyeball 眼球 accessory organs of eyeball 眼附属器

Section 1 Eyeball Ⅰ. Shape of eyeball anterior and posterior poles 前、后极 anterior pole Axis of eyeball 眼轴:a line joining the two poles Optic axis 视轴:a line joining the center of the pupil to the fovea centralis黄斑中央凹 Equator 赤道: an imaginary line encircling the eyeball, midway between anterior and posterior poles posterior pole

Ⅱ.Structure of eyeball 1. Walls of eyeball Fibrous tunic of eyeball Cornea 角膜 Sclera 巩膜 Iris 虹膜 Cilliary body 睫状体 Choroid 脉络膜 Vascular tunic of eyeball Pars iridica retinae 虹膜部 Pars ciliaris retinae 睫状体部 Pars optica retinae 视部 Pars caeca retinae盲部 Retina 视网膜

(1) Fibrous tunic 纤维膜 (outer layer) Cornea 角膜: anterior 1/6； Ⅱ Wall of eyeball (1) Fibrous tunic 纤维膜 (outer layer) Cornea 角膜: anterior 1/6； a nonvascular, transparent portion； supplied richly by nerves; because it is curved, the cornea helps focus light. 感觉神经丰富，故感觉敏锐。有屈光作用 Ⅱ

(1) Fibrous tunic 纤维 膜 Sclera巩膜: Walls of eyeball posterior 5/6, consists of fibrous connective tissue having protection and surpporting for eyeball, posteriorly it contineus with the sheath of optic n.

sinus venous sclerae 巩膜静脉窦: lies beneath the junction of cornea and sclera角膜与巩膜交界处, and is irregular circular canal. cribriform plate of sclera 巩膜筛板 cornea Sinus venous sclerae sclera

iris 虹膜 (2) Vascular tunic 血管膜 (middle layer): Wall of eyeball (2) Vascular tunic 血管膜 (middle layer): iris 虹膜 lies the anterior part of the vascular tunic, and is a thin contractile membrane with a central opening, the pupil 瞳孔 iridocorneal angle 虹膜角膜角 sphincter pupillae 瞳孔括约肌 dilator pupillae 瞳孔开大肌

Behind the iris，may be divided into eyeball Ciliary body 睫状体: Behind the iris，may be divided into a) ciliary ring 睫状环 b) ciliary processes 睫状突: 60~80条, producing aqueous humor房水 ciliary muscle睫状肌 ciliary zonules 睫状小带 d) 作用： 调节晶状体的曲度 secrete the aqueous humor房水 ciliary zonules

choroid 脉络膜 function： Nutrition 营养作用 eyeball choroid 脉络膜 Thin, highly vascular in posterior 2/3 of eye Contains brown pigmented cells and dense capillary plexus function： Nutrition 营养作用 Absorb the disperse light 吸收分散光作用。

(3) Internal tunic of eyeball内膜— retina 视网膜 Wall of eyeball (3) Internal tunic of eyeball内膜— retina 视网膜 division: 以锯状缘ora serrata为界 a. Pars caeca retinae盲部 : b. Pars optica retinae视部 : pars iridica retinae虹膜部 pars ciliaris retinae睫状体部 无感光细胞，仅有色素上皮层 脉络膜部: 有感光作用

The retina consists of two layers: Wall of eyeball 2) structure: The retina consists of two layers: pigment epithelial layer色素上皮层 nervus layer神经层 ：consist of three layers of cells Photoreceptor cells：感光细胞 Cone cell 视锥细胞 Rod cell 视杆细胞 Rod cell Cone cell Pigment cell layer

ganglion cell 节细胞, whose axons form the optic n. fibers Wall of eyeball bipolar cell 双极细胞 ganglion cell 节细胞, whose axons form the optic n. fibers Ganglion cell Bipolar neuron Rod cells Cone cells Pigment cell layer

Wall of eyeball Optic disc 视神经盘 (blind spot盲点), located medial to posterior pole of eye, and consists of optic nerve fibers and at where there are central a.and v. of retina Macula lutea 黄斑 Lies lateral about 3.5 mm to optic disc, a shallow depression, and is yellowish in color

Wall of eyeball Fovea centralis 中央凹, is an aera of greatest visual acuity and is completely free of blood vessels (concentration of cone cells). The pigment epithelial layer色素上皮层 absorbs light that enter the eyeball preventing backscatter (blurring of vision)

2. Contents of eyeball 眼球内容物 (1)  Aqueous humor房水 1) Chamber of eye 眼房: lies between cornea and lens, and divided by iris into： anterior chamber 眼前房 posterior chamber 眼后房

Helps maintain constant pressure in eyeball Contents of eyeball   2) Aqueous humor房水 A clear watery fluid that fills chamber of eye，secreted by ciliary body. Functions Helps focus light Helps maintain constant pressure in eyeball Helps nourish the lens and cornea

Production and circulation of aqueous humor房水: pupil secreted by the ciliary body posterior chamber anterior chamber  iridocorneal angle sinus venosus sclera anterior ciliary vein睫前静脉 ophthalmic vein sinus venosus sclera

position：lis behind the iris，anterior to the vitreous body 玻璃体. Contents of eyeball (2)  Lens 晶状体 position：lis behind the iris，anterior to the vitreous body 玻璃体. shape： Transparent biconvex structure, covered by an elastic transparent capsule which is connected by the ciliary zonules睫状小带(suspensory lig.晶状体悬韧带 )to the ciliary process

Contents of eyeball Structure: lens capsule 晶状体囊 cortex of lens 晶状体皮质 lens nucleus 晶状体核 Its shape is changed by the ciliary muscle: for near vision, the ciliary muscle contracts and the lens rounds up, while for distant vision the lens flattens out, so that the eye may be focused on distant objects

Helps maintain the shape of eyeball and supports the retina Contents of eyeball (3)  Vitreous body 玻璃体 Consists of colorless, transparent jelly-like substance胶状物质in which there is a meshwork of fine fibrils, occupies the space between lens and retina Helps maintain the shape of eyeball and supports the retina

(4) Refractive media:屈光系统 include Contents of eyeball (4) Refractive media:屈光系统 include Cornea 角膜、 aqueous humor 房水、lens 晶状体 vitreous body 玻璃体 Bend entering light waves and focus them on the retina

Section2. Accessory organs Ⅰ.  Eyelids眼睑: upper and lower ，consist of 5 layers, ①Skin 皮肤 ②subcutaneous adipose tissue 皮下组织, ③musclar layer 肌层: orbicularis oculi ④tarsus睑板： formed by dense connective tissue (tarsal glands) ⑤ palpebral conjunctiva 睑结膜

Palpebral conjunctiva 睑结膜: Accessory organs of eye Ⅱ.Conjunctiva 结膜: thin mucous membrane 3 parts: Palpebral conjunctiva 睑结膜: lining inner surface of eyelids; Bulbar conjunctiva 球结膜: lining anterior part of sclera; Conjunctival fornix 结膜穹隆 (superior and inferior): the reflected part of the conjunctiva from the superior and inferior eyelids onto the eyeball. Conjunctival sac 结膜囊

Ⅲ.Lacrimal apparatus 泪器 1. Lacrimal gland 泪腺: Accessory organs of eye Ⅲ.Lacrimal apparatus 泪器 1. Lacrimal gland 泪腺: 2. Lacrimal passages 泪道:   lacrimal punctum泪点: on each eyelid margin near medial angle lacrimal ductules 泪小管: in each lid, pass medially, join and enter lacrimal sac Lacrimal sac 泪囊: in fossa for lacrimal sac, opening into nasolacrimal duct Nasolacrimal duct 鼻泪管: opening into inferior nasal meatus

Ⅳ.Extraocular m. 眼外肌: 7 Rectuses直肌: 4 superior rectus 上直肌 Accessory organs of eye Ⅳ.Extraocular m. 眼外肌: 7 levator palpebrae superioris上睑提肌: elvates the upper eyelid. Rectuses直肌: 4 superior rectus 上直肌 inferior rectus 下直肌, medial rectus 内直肌 lateral rectus 外直肌   Obliquuses 斜肌: 2 Superior obliquus  Inferior obliquus

Accessory organs of eye Muscle Action N. supply levator palpebrae superioris elvates upper eyelid Ⅲ Superior rectus turns eyeball superomedially Ⅲ Inferior rectus turns eyeball inferomedially Ⅲ Medial rectus turns the eyeball medially Ⅲ Lateral retus turns the eyeball laterally Ⅵ Superior obliquus turns eyeball inferolaterally Ⅳ Inferior obliquus turns eyeball superolaterally Ⅲ

Accessory organs of eye

Ⅴ. Connective Tissues in the Orbit 眶内结缔组织 Accessory organs of eye Ⅴ. Connective Tissues in the Orbit 眶内结缔组织 1. adipose body of orbit 眶脂体 lies between sheath of eyeball and the orbit acts as a protective cushion and shock sorber for the eyeball 2. orbital fasciae 眶筋膜 a. periorbita 眶骨膜 b. fascial sheath of eyeball 眼球筋膜鞘 c. sheath of ocular muscles 眼肌筋膜鞘 d . orbital septum 眶隔

Section 3. The vessels and nerves of eye Ⅰ. Vessels of eye 1. Artery 动脉 (1)Ophthalmic a.眼动脉: Arises from the internal carotid a. Branches: 1) central a. of retina 视网膜中央动脉 Enters optic nerve, passes toward the optic disk and then fans out to supply the retina

The vessels and nerves of eye 1) central a. of retina 视网膜中央动脉 branches: superior nasal arteriole of retina 视网膜鼻侧上小动脉 inferior nasal arteriole of retina 视网膜鼻侧下小动脉 superior temporal arteriole of retina 视网膜颞侧上小动脉 inferior temporal arteriole of retina 视网膜颞侧下小动脉

The vessels and nerves of eye 2) short posterior ciliary a.睫状后短动脉: 又称脉络膜动脉Choroidal artery 3) long posterior ciliary a . 睫状后长动脉: 又称虹膜动脉; 4) anterior ciliary a.睫前动脉

The vessels and nerves of eye Ⅱ.Vein 静脉 (1） central v. of retina 视网膜中央静脉 (2） vortex vein 涡静脉 (3）anterior ciliary veins 睫前静脉 (4）眼静脉Ophthalmic v. a)Superior ophthalmic v. b) Inferior ophthalmic v

The vessels and nerves of eye 视神经 optic nerve: 传导视觉 动眼神经 oculomotor n. 滑车神经 trochlear n.支配上斜肌 展神经 abducent n.支配外直肌 眼神经ophthalmic n. 面神经facial n.: 管理泪腺分泌.

superior temporal arteriole of retina superior nasal arteriole of retina inferior temporal arteriole of retina inferior nasal arteriole of retina

小结 眼球：屈光---角膜、房水、晶状体、玻璃体 调节---虹膜、睫状体 营养---脉络膜、房水 感光---视网膜 眼球保护：眼睑---睑板、眼轮匝肌、上睑提肌 结膜---睑结膜、球结膜、结膜穹 泪器---泪腺、泪道 眼球运动：眼外肌---四直两斜一提肌

Sinus venosus sclerae Ciliary Muscle Iridocorneal angle Dilator Pupillae Sphincter Pupillae Lens Ciliary Processes ciliary zonule

chapter14 视器The Visual Organ composition    外膜 fibrous tunic ： 中膜 vascular tunic： 内膜retina 视网膜： 角膜cornea 巩膜sclera 虹膜iris 睫状体ciliary body 脉络膜choroid walls 眼内容物 脉络膜部choroidal part: pars opticaretinae 睫状体部 pars ciliaris 虹膜部 pars iridiac Eyeball 眼球 accessory organs of eyeball 眼附属器: 视部 pars caeca retinae 盲部 房水 aqueous humor 晶状体 lens 玻璃体 vitreous body 眼睑、泪器、眼外肌、眶脂体、眶筋膜

3. Contents of eyeball 晶状体的调节 视近物时： 睫状肌收缩，向前牵引睫状突 晶状体变厚, 屈光力加强； 睫状小带松弛 睫状肌舒张 视远物时： 睫状小带紧张 晶状体被拉薄, 屈光力下降。