PowerPoint ® Lecture Slide Presentation by Patty Bostwick-Taylor, Florence-Darlington Technical College Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings PART C 3 Tissues

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Objectives  List the four major tissue types in the body  Describe the general characteristics and functions of epithelial cells  Name the types of epithelium and identify an organ in which each is found.

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Body Tissues  Tissues  Groups of cells with similar structure and function  Histology- study of tissues  Four primary types  Epithelial tissue (epithelium)  Connective tissue  Muscle tissue  Nervous tissue

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelial Tissues  Locations  Membraneous  Body coverings  Body linings  Glandular tissue  Functions  Protection  Absorption  Filtration  Secretion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelium Characteristics  Cells fit closely together and often form sheets  The apical surface is the free surface of the tissue  The lower surface of the epithelium rests on a basement membrane  Avascular (no blood supply)  Regenerate easily if well nourished

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Epithelium Characteristics Figure 3.17a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Classification of Epithelia  Number of cell layers  Simple—one layer  Stratified—more than one layer Figure 3.17a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Classification of Epithelia  Shape of cells  Squamous  flattened  Cuboidal  cube-shaped  Columnar  column-like Figure 3.17b

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple squamous  Single layer of flat cells  Usually forms membranes  Lines body cavities  Lines lungs and capillaries

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18a

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple cuboidal  Single layer of cube-like cells  Common in glands and their ducts  Forms walls of kidney tubules  Covers the ovaries

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18b

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Simple columnar  Single layer of tall cells  Nucleus at bottom of cell  Often includes mucus-producing goblet cells  Lines digestive tract  Epithelial membranes that line cavities open to the body exterior- mucosae mucous membranes

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18c

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia  Pseudostratified columnar  Single layer, but some cells are shorter than others  Often looks like a double layer of cells  Sometimes ciliated, such as in the respiratory tract  May function in absorption or secretion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Simple Epithelia Figure 3.18d

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Stratified squamous  More durable  Cells at the apical surface are flattened  Found as a protective covering where friction is common  Locations  Skin  Mouth  Esophagus

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia Figure 3.18e

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Stratified cuboidal—two layers of cuboidal cells  Stratified columnar—surface cells are columnar, cells underneath vary in size and shape  Stratified cuboidal and columnar  Rare in human body  Found mainly in ducts of large glands

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia  Transitional epithelium  Shape of cells depends upon the amount of stretching  Lines organs of the urinary system

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Stratified Epithelia Figure 3.18f

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Glandular Epithelium  Gland  One or more cells responsible for secreting a particular product  Product made is called a secretion

Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Glandular Epithelium  Two major gland types  Endocrine gland  Ductless since secretions diffuse into blood vessels  All secretions are hormones  Exocrine gland  Secretions empty through ducts to the epithelial surface  Include sweat and oil glands