Unit 3 Learning Objectives

Belzer - Histology and Integumentary systems

Histology

The study of tissues

Pathology

The study of disease

Top side of epithelial cells

Apical side. Interacts with the lumen (“empty space”).

Bottom side of epithelial cells

Basal side. Always attached to connective tissue.

Tight junction (Epithelial)

Seals cells together. Prevents molecules from leaking through, close to apical side of cell.

Adherens junction (Epithelial)

“Protein zipper” - Joins an actin bundle in one cell to a similar one in a neighboring cell. Very strong, will sit below a tight junction.

Desmosome junction (Epithelial)

Strongest junctions - Joins intermediate filaments in one cell to another

Gap/Communication Junctions  (Epithelial)

Holes/channels that allow the cells to communicate to its neighbor by allowing polar ions and molecules to pass through.

Simple squamous epithelium

Found in lining of blood vessels (endothelium) & anywhere diffusion/filtration need to occur rapidly.

Simple cuboidal epithelium

Makes up glands and ducts, allows for reabsorption & secretion. Found in thyroid and kidneys.