Tissue Types:
1.) Epithelial Tissue:
● Surfaces, coverings, and linings.
● Forms glands.
● Locations:
○ Body surface.
○ Inner linings of organs.
● Tight barriers, on surfaces.
● Closely packed cells held together by cell junctions; little intercellular
material.
● Apical surface (towards lumen), basal surface (attached at the bottom to
basement membrane), and lateral surfaces (sides).
○ Apical / Free Surface - Top of layers. The lining of organs, the
exterior of the body.
○ Basal Surface - Bottom of layers attached to the basement
membrane.
○ Basement membrane - Extracellular material between epithelial
and connective tissue.
,● Has a nerve supply.
● Avascular - No blood supply.
○ Instead, connective tissue diffuses blood upwards.
● Makes direct contact with the external environment.
○ The only tissue that does.
● High rate of cell division for renal and repair.
● Functions:
○ Protection
○ Filtration
○ Secretion
○ Absorption
○ Excretion
● Types of Epithelial Tissue: ( * Note - Simple = 1 , Stratified = Many * )
○ Simple Squamous:
■ Single layer of flat cells.
● Think - SQU - Squamous, SQU - Squished
■ Single flat nucleus.
■ Functions: Diffusion and filtration.
■ Locations:
● Kidneys
● Alveoli - Air Sacs of Lungs
● Blood Vessels
● Abdominal Cavity Lining
■ Look For:
● Single Layer
● Flat Cells
● Irregular Borders
, ○ Simple Cuboidal:
■ Single layer of cube-shaped cells.
● Think - CUB - Cuboidal, CUB - Cube.
■ Round central nucleus.
■ Functions: Secretion and absorption.
■ Locations:
● Kidneys
● Digestive Tract
■ Look For:
● Single Layer
● Sube-Shaped Cells
● Round Nucleus
● Rings / Ovals
1.) Epithelial Tissue:
● Surfaces, coverings, and linings.
● Forms glands.
● Locations:
○ Body surface.
○ Inner linings of organs.
● Tight barriers, on surfaces.
● Closely packed cells held together by cell junctions; little intercellular
material.
● Apical surface (towards lumen), basal surface (attached at the bottom to
basement membrane), and lateral surfaces (sides).
○ Apical / Free Surface - Top of layers. The lining of organs, the
exterior of the body.
○ Basal Surface - Bottom of layers attached to the basement
membrane.
○ Basement membrane - Extracellular material between epithelial
and connective tissue.
,● Has a nerve supply.
● Avascular - No blood supply.
○ Instead, connective tissue diffuses blood upwards.
● Makes direct contact with the external environment.
○ The only tissue that does.
● High rate of cell division for renal and repair.
● Functions:
○ Protection
○ Filtration
○ Secretion
○ Absorption
○ Excretion
● Types of Epithelial Tissue: ( * Note - Simple = 1 , Stratified = Many * )
○ Simple Squamous:
■ Single layer of flat cells.
● Think - SQU - Squamous, SQU - Squished
■ Single flat nucleus.
■ Functions: Diffusion and filtration.
■ Locations:
● Kidneys
● Alveoli - Air Sacs of Lungs
● Blood Vessels
● Abdominal Cavity Lining
■ Look For:
● Single Layer
● Flat Cells
● Irregular Borders
, ○ Simple Cuboidal:
■ Single layer of cube-shaped cells.
● Think - CUB - Cuboidal, CUB - Cube.
■ Round central nucleus.
■ Functions: Secretion and absorption.
■ Locations:
● Kidneys
● Digestive Tract
■ Look For:
● Single Layer
● Sube-Shaped Cells
● Round Nucleus
● Rings / Ovals