5.2 Flashcards
Epithelial tissue is characterized as simple, stratified, or pseudostratified. What does this mean?
- Simple epithelium – A single layer of cells.
- Stratified epithelium – Multiple layers of cells.
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Pseudostratified epithelium – Appears layered due to nuclei at
different levels, but all cells touch the basement membrane.
What are the three basic shapes of epithelial cell?
Squamous, cuboidal, and columnar
Simple squamous
Description: Delicate and thin, allows passage of gas or liquid
Location: Lining surfaces involved in absorption/filtration
Examples: Inner lining of the lungs (gas exchange), filtration membranes of kidneys
Simple cuboidal
Description: Single layer of cubic cells, involved in secretion and absorption
Location: Glands and ducts, organ surfaces
Examples: Surface of ovaries, thyroid gland, ducts of liver, pancreas, kidney, and salivary glands
Simple columnar
Description: Tall, closely packed cells, specialized for absorption/secretion
Location: Lining of the gastrointestinal (GI) tract
Examples: Stomach to rectum, elongated and closely packed together
Stratified squamous
Description: Multiple layers, protects against mechanical and chemical stress
Location: Areas exposed to friction or chemical stress
Examples: Lining of the mouth, esophagus, vagina, and rectum
Pseudostratified columnar
Description: Appears stratified but is a single layer, often ciliated
Location: Respiratory and reproductive tracts
Examples: Lining of the respiratory tract, portions of the male reproductive tract
Transitional
Description: Stretchable, changes shape depending on expansion
Location: Areas requiring expansion and contraction
Examples: Urinary bladder, ureters, urethra, and kidney calyxes
