上皮细胞的种类有什么?分别是什么作用?
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/31 17:10:28
上皮细胞的种类有什么?分别是什么作用?
上皮细胞的种类有什么?分别是什么作用?
上皮细胞的种类有什么?分别是什么作用?
上皮细胞变成组织——上皮组织,上皮组织有人体外皮——人最大的器官,肠也有上皮细胞,口腔也有,胃也有上皮细胞 上皮细胞是保护细胞,可分泌保护液 滋润液和消化液,口水也是消化液.
上皮组织结构上可以分为两组取决于层数的,它是组成。 Epithelial tissue that is only one cell thick is known as simple epithelium.上皮组织,这只是一个细胞的厚度为单层上皮而闻名。 If it is two or more cells thick, it is known as stratified epithelium.如果...
全部展开
上皮组织结构上可以分为两组取决于层数的,它是组成。 Epithelial tissue that is only one cell thick is known as simple epithelium.上皮组织,这只是一个细胞的厚度为单层上皮而闻名。 If it is two or more cells thick, it is known as stratified epithelium.如果是两个或多个单元格厚,它被称为复层上皮。
However, when taller simple epithelial cells (see columnar , below) are viewed in cross section with several nuclei appearing at different heights, they can be confused with stratified epithelia.然而,当高大简单上皮细胞(见柱状 ,下文)第看待两岸在几个不同高度的原子核出现,它们可以混淆分层上皮。 This kind of epithelium is therefore described as "pseudostratified" epithelium.这种上皮种,因此称为“假”上皮。
Regardless of the type, any epithelium is separated from the underlying tissue by a thin layer of connective tissue known as the basement membrane.无论类型,任何上皮组织分离的基础,作为一个著名的基底膜结缔组织的薄层。 The basement membrane provides structural support for the epithelium and also binds it to neighbouring structures.基底膜上皮结构提供了支持,并把它绑定到邻近的结构。
鳞状细胞具有薄,平板外观。 They fit closely together in tissues; providing a smooth, low-friction surface over which fluids can move easily.他们适合在组织密切合作,提供一个平稳,低摩擦表面的液体能够在移动方便。 The shape of the nucleus usually corresponds to the cell form and helps to identify the type of epithelium.原子核的形状通常对应的细胞形态,以帮助确定的上皮细胞类型。 Squamous cells tend to have horizontally flattened, elliptical (oval or shaped like an egg) nuclei because of the thin flattened form of the cell.鳞状细胞往往有横向扁平,椭圆形(椭圆形或像一个鸡蛋形的)核,因为薄扁平的细胞形态。 Classically, squamous epithelia are found lining surfaces utilizing simple passive diffusion such as the alveolar epithelium in the lungs.经典,鳞状上皮细胞表面发现衬里利用,如简单的被动扩散肺泡上皮细胞在肺部。 Specialized squamous epithelia also form the lining of cavities such as the blood vessels ( endothelium ) and pericardium ( mesothelium ) and the major cavities found within the body.还专门鳞状上皮的形成(血管衬腔,如内皮细胞 )和心包 ( 间皮 ),并在体内发现的主要腔。 :) :)
Cuboidal 立方形 As their name implies, cuboidal cells are roughly cuboidal in shape, appearing square in cross section.正如其名称所示,大致立方立方细胞的形状,出现在横截面。 Each cell has a spherical nucleus in the centre.每个单元都有一个球形核的中心。 Cuboidal epithelium is commonly found in secretive or absorptive tissue: for example the (secretive) exocrine gland the pancreas and the (absorptive) lining of the kidney tubules as well as in the ducts of the glands.立方上皮常见于遮遮掩掩,或吸收组织:例如(秘密)外分泌腺胰腺和肾脏的(吸收)内衬管以及在腺体的导管。 They also constitute the germinal epithelium that covers the female ovary.他们也构成了生发上皮 ,涵盖了女性卵巢。
Columnar 柱状 Columnar epithelial cells are elongated and column-shaped.柱状上皮细胞伸长和列形。 Their nuclei are elongated and are usually located near the base of the cells.拉长的细胞核,通常是附近的基地位于细胞。 Columnar epithelium forms the lining of the stomach and intestines.柱状上皮构成了胃和肠的内层。 Some columnar cells are specialized for sensory reception such as in the nose, ears and the taste buds of the tongue.有些柱状细胞是专门用于接收,如感觉鼻子,耳朵和舌头的味蕾。 Goblet cells (unicellular glands) are found between the columnar epithelial cells of the duodenum.杯状细胞(单细胞腺)被发现十二指肠之间的柱状上皮细胞。 They secrete mucus, which acts as a lubricant.它们分泌黏液,它作为一个润滑剂。
Pseudostratified 假 These are simple columnar epithelial cells whose nuclei appear at different heights, giving the misleading (hence "pseudo") impression that the epithelium is stratified when the cells are viewed in cross section.这些都是简单的柱状,其细胞核出现在不同的高度,给误导(因此“伪”)印象是分层的上皮细胞时,在横截面看上皮细胞。 Pseudostratified epithelium can also possess fine hair-like extensions of their apical (luminal) membrane called cilia .假上皮细胞也可以拥有(腔)膜称为细毛状扩展其顶端的纤毛 。 In this case, the epithelium is described as "ciliated" pseudostratified epithelium.在这种情况下,上皮细胞被称为“纤毛”假上皮。 Cilia are capable of energy dependent pulsatile beating in a certain direction through interaction of cytoskeletal microtubules and connecting structural proteins and enzymes.纤毛是在一定的方向依赖能源能够通过互动搏动跳动细胞骨架微管及连接结构蛋白和酶。 The wafting effect produced causes mucus secreted locally by the goblet cells (to lubricate and to trap pathogens and particles) to flow in that direction (typically out of the body).该效应产生的原因飘出分泌黏液的杯状细胞在本地(润滑和病原体和捕获粒子)流在这个方向(通常出体外)[ edit ] Stratified epithelium [ 编辑 ] 复层上皮
收起