HLSC 2465U Chapter Notes - Chapter 5: Stratified Squamous Epithelium, Transitional Epithelium, Respiratory Tract
Document Summary
Surface epithelia covers and lines the body. Form a protective barrier, diffusion, absorption, excretion. Avascular get nutrients from basement membrane but produced by diffusion of. Simple epithelia: single layer of cells, selective diffusion, absorption/secretion, little protection, alveoli, blood vessels, body cavities, simple epithelia may have microvilli or cilia. Simple squamous: resemble scales, lining surfaces such as blood capillaries, pleural, pericardial cavities. Simple cuboidal: appears square, nucleus is round in center of the cell, usually lines small ducts and tubules, excretory, secretory, absorptive functions. Simple columnar: cells are taller, small intestines, stomach, absorptive, with cilia, it propels fluid and particles, female reproductive tract (fallopian tube) Pseudostratified columnar ciliated epithelium: it is actually one layer of cells, generally have cilia on them, touch the basement membrane, respiratory. Stratified epithelia: 2/more layers, physical stresses or surface is exposed, permeable to water (keratin) Stratified squamous: withstand abrasion, oral cavity, vagina, anus, oesophagus, keratinized waterproof barrier.