1. Epithelial Tissue
Characteristics:

2. Simple Squamous Epithelial
Description: Single layer of flat cells.
Location: lining of lungs and heart, blood vessels, ventral cavity and at kidney glomeruli.
Function: allows passage of materials by diffusion where protection isn’t as important; also aids in secretion

3. Stratified Squamous Epithelial
These keratinized epithelial cells will
Be sloughed off.
Description: multiple layers of flat cells (basal layer is usually columnar or cuboidal).
Location: skin, lining of the cheek.
Function: creates a barrier that protects body from abrasion
Apical Layer
Basal Layer

4. Simple Cuboidal Description: Single layer of cube-shaped cells.
Location: small ducts of glands, kidney tubules, surface of ovary.
Function: secretion & absorption
Cell is as wide as it is high. One
central nucleus

5. Simple Cuboidal Cells closely packed together and touching one another
Lumen:
Inside space of
Tubular structure
Cells closely packed together and touching one another
Has a basal surface and apical surface
Avascular
Sits on a basement membrane (can difficult to see on slide)
Apical
Surface
Nucleus
Basal
Surface

6. Non- Ciliated Simple Columnar
Description: Single layer of non-ciliated rectangular cells; contain goblet cells and sometimes microvilli.
Location: GI tract, ducts, gallbladder
Function: secretion and absorption

7. Nuclei lie near base of cell
Goblets secrete mucous at apical surface to lubricate lining of GI, respiratory, reproductive and urinary systems.
Microvilli increase surface area for absorption.
Simple Columnar Cells
Goblet Cell
Nucleus
Goblet Cell

8. Pseudostratified Ciliated Columnar Epithelium
Description: Appears stratified because nuclei are at varying levels.
Location: Ciliated lines airways of upper respiratory tract (trachea).
Function: Mucus from Goblets traps foreign particles and are swept away by cilia.
Goblet Cells

9. Goblet Cells secreting mucus
Cilia
Nuclei at varying levels

10. Epithelial and Connective1
1 – pseudostratified columnar epithelial
2- simple cuboidal epithelial
3- hyaline cartilage connective tissue 2 3

11. Loose Areolar Connective Tissue
Description: gel-like matrix with elastic & collagen fibers.
Location: lies underneath epithelia, wraps capillaries, and can package organs
Function: wraps and cushions organs; plays important role in inflammation and immune response

12. Loose Areolar Connective Tissue
Fibroblast CELLS
MATRIX
FIBER
Elastic Fiber
Collagen Fiber
(thicker pink ones)
Loose Areolar
Connective Tissue
GROUND SUBSTANCE

13. Dense Regular Connective Tissue
Description: Mostly collagen fibers with fibroblasts between rows. Matrix looks white and shiny.
Location: Tendons, ligaments and aponeuroses.
Function: Strong attachment!

14. Dense Regular CT (magnified)
Fibroblasts
Fibers are
mostly
Collagen.

15. Reticular Connective Tissue
Reticular Cells
Description: Network of interlacing reticular fibers & reticular cells
Location: Found in liver, spleen, lymph nodes, & red bone marrow.
Function: Acts as a filter in spleen and lymph nodes.
Blue staining
Reticular fibers

16. Reticular Connective Tissue
Remember that connective tissue is vascular. (Avascular epithelial tissue depends on diffusion of nutrients and waste through blood vessels in CT).
Blood vessel:
Single layer of
Epithelial cells
forms vessel tube.

17. Reticular CT 1 2 1- Reticular cells 2- Blood vessel3 2
1- Reticular cells
2- Blood vessel
3- Reticular fibers