Simple Squamous Epithelium
• Single layer of flat cells– lines blood vessels (endothelium), closed body cavities
(mesothelium)– very thin --- controls diffusion, osmosis and filtration
What is the primary function of this tissue (protection or transport)? (Hint: What is its function as an endothelium,…as mesothelium?)
Examples of Simple Squamous Epithelium
• Section of intestine showing serosa
• Surface view of lining of peritoneal cavity
Is this endothelium, mesothelium, or neither?
Simple Cuboidal Epithelium
• Single layer of cube-shaped cells viewed from the side
Where would you find simple cuboidal epithelium in the body? Does it typically function in protection or transport in these locations?
Example of Simple Cuboidal Epithelium
• Sectional view of kidney tubulesWhy do some cells look as if they do not have a nucleus?
Nonciliated Simple Columnar
• Unicellular glands =goblet cells secrete mucus– lubricate GI, respiratory, reproductive and urinary systems
• Microvilli = fingerlike projections of cell membraneDescribe the differences between cilia and microvilli in terms of
both their structure and function. Are you likely to find them on the same tissue? Why or Why not?
Example: Nonciliated Simple Columnar Epithelium
• Section from small intestineThe term “brush border” is often used to describe
this tissue. What does it refer to?
Ciliated Simple Columnar Epithelium
• Single layer rectangular cells with cilia• Mucus from goblet cells moved along by cilia
Example Ciliated Simple Columnar Epithelium
• Section of uterine tubeWhat is another name for this organ?
Stratified Squamous Epithelium• Several cell layers thick• Surface cells flat• Keratinized = surface cells
dead and filled with keratin– Example…?
• Nonkeratinized = no keratin in moist, living cells at apical surface– Example …?
What is the primary function of this epithelium?
If this epithelium is a portion of a mucus membrane, where does the mucus come from?
Stratified Cuboidal Epithelium
• Multilayered• Surface cells cuboidal– rare (only found in
sweat gland ducts & male urethra)
Stratified Columnar Epithelium
• Multilayered• Surface cells columnar• Rare (very large ducts & part of male urethra)
• Multilayered • Surface cells varying in shape
from round to flat if stretched• Lines hollow organs of the urinary
tract that expand from within
Transitional Epithelium
List the expandable organs of the urinary tract.