© 2015 Pearson Education, Inc. Body Tissues  Tissues  Groups of cells with similar structure and function  Four primary types:

© 2015 Pearson Education, Inc. Epithelial Tissues  Locations:   Functions: 

© 2015 Pearson Education, Inc. Epithelium Characteristics  Cells fit ______________-and often form _______  The _____ surface is the ____ surface of the tissue  The lower surface of the epithelium rests on a _______________  _________ (no blood supply)  ____________ easily if well nourished

© 2015 Pearson Education, Inc. Figure 3.17a Classification and functions of epithelia. ______ surface _______ surface ______ surface _________ ____________ (a) Classification based on number of ____________

© 2015 Pearson Education, Inc. Classification of Epithelia  Number of cell layers  Simple—__________  Stratified—_______________

© 2015 Pearson Education, Inc. Classification of Epithelia  Shape of cells  Squamous  ______________________  Cuboidal  ______________________  Columnar  ______________________

© 2015 Pearson Education, Inc. Figure 3.17b Classification and functions of epithelia. ____________ _________ __________ (b) Classification based on cell shape

© 2015 Pearson Education, Inc. Figure 3.17c Classification and functions of epithelia. Diffusion and filtration Secretion in serous membranes Protection Secretion and absorption; ciliated types propel mucus or reproductive cells Protection; these tissue types are rare in humans Protection; stretching to accommodate distension of urinary structures (c) Function of epithelial tissue related to tissue type Number of layers Cell shape One layer: simple epithelial tissues More than one layer: stratified epithelial tissues Squamous Cuboidal Columnar Transitional

© 2015 Pearson Education, Inc. Simple Epithelia  Simple squamous  ______________________  Location—usually forms membranes  Lines ____________________  Forms walls of ______________  Forms serous membranes (serosae) that line and cover organs in ventral cavity  Functions in ____________________________in membranes

© 2015 Pearson Education, Inc. Figure 3.18a Types of epithelia and their common locations in the body. Nucleus of squamous epithelial cell Basement membrane Air sacs of lungs Nuclei of squamous epithelial cells (a) Diagram: Simple squamous Photomicrograph: Simple squamous epithelium forming part of the alveolar (air sac) walls (275×).

© 2015 Pearson Education, Inc. Simple Epithelia  Simple cuboidal  _________ layer of cube-like cells  Locations:  Common in _____________________  Forms walls of _______________  Covers the surface of _________________  Functions in ____________________; ciliated types propel _______________________

© 2015 Pearson Education, Inc. Figure 3.18b Types of epithelia and their common locations in the body. Nucleus of simple cuboidal epithelial cell Basement membrane Simple cuboidal epithelial cells Basement membrane Connective tissue (b) Diagram: Simple cuboidal Photomicrograph: Simple cuboidal epithelium in kidney tubules (250×).

© 2015 Pearson Education, Inc. Simple Epithelia  Simple columnar  _______________________  _____________secrete mucus  Location:  _____________________________________  Mucous membranes (mucosae) line body cavities opening to the exterior  Functions in __________________; ciliated types propel _________________________

© 2015 Pearson Education, Inc. Figure 3.18c Types of epithelia and their common locations in the body. Basement membrane Mucus of a goblet cell Nucleus of simple columnar epithelial cell Simple columnar epithelial cells (c) Diagram: Simple columnar Photomicrograph: Simple columnar epithelium of the small intestine (575×).

© 2015 Pearson Education, Inc. Simple Epithelia  Pseudostratified columnar  All cells rest on a _______________________  ______________ layer, but some cells are shorter than others giving a ______ (pseudo) impression of _____________  Location:  ____________, where it is ciliated and known as pseudostratified ciliated columnar epithelium  Functions in __________________

© 2015 Pearson Education, Inc. Figure 3.18d Types of epithelia and their common locations in the body. (d) Diagram: Pseudostratified (ciliated) columnar Photomicrograph: Pseudostratified ciliated columnar epithelium lining the human trachea (560×). Basement membrane Pseudo- stratified epithelial layer Cilia Connective tissue

© 2015 Pearson Education, Inc. Stratified Epithelia  Stratified squamous  Named for cells present at the ____ (apical) surface, which are _________  Functions as a protective covering where ______ is common  Locations—lining of the: 

© 2015 Pearson Education, Inc. Figure 3.18e Types of epithelia and their common locations in the body. Basement membrane Connective tissue Stratified squamous epithelium (e) Diagram: Stratified squamous Photomicrograph: Stratified squamous epithelium lining of the esophagus (140×). Nuclei

© 2015 Pearson Education, Inc. Stratified Epithelia  Stratified cuboidal—__________ of cuboidal cells; functions in protection  Stratified columnar—surface cells are __________. and cells underneath vary in ________; functions in _________  Stratified cuboidal and columnar 

© 2015 Pearson Education, Inc. Stratified Epithelia  Transitional epithelium  Composed of modified stratified squamous epithelium  Shape of cells depends upon the ________________________  Functions in stretching and the ability to return to normal shape  Locations: ______________________

© 2015 Pearson Education, Inc. Figure 3.18f Types of epithelia and their common locations in the body. Basement membrane Connective tissue Transi- tional epithelium Transitional epithelium (f) Diagram: Transitional Photomicrograph: Transitional epithelium lining of the bladder, relaxed state (270×); surface rounded cells flatten and elongate when the bladder fills with urine.

© 2015 Pearson Education, Inc. Glandular Epithelium  Gland  One or more cells responsible for _____________________________  Secretions contain protein molecules in an aqueous (water-based) fluid  Secretion is an _______________

© 2015 Pearson Education, Inc. Glandular Epithelium  Two major gland types  Endocrine gland  _________; secretions diffuse into blood vessels  All secretions are ____________  Examples include thyroid, adrenals, and pituitary

© 2015 Pearson Education, Inc. Glandular Epithelium  Two major gland types  Exocrine gland  Secretions empty ___________to the epithelial surface  Include _______________, liver, and pancreas  Includes both internal and external glands