Epithelium Flashcards
(41 cards)
Absorption
Active take up of molecules (active/cell uses energy)
Secretion
Active release of molecules (active/cell uses energy)
What do absorption and secretion usually involve?
Microvilli (extensions to increase surface area)
Diffusion
Molecules move down concentration gradient (passive/no energy)
Filtration
Plasma (fluid component of blood) leaks across capillary walls (passive/no energy)
Propulsion
Cilia drive fluid along surface of epithelium
Sliding
Cilia sliding across surface of epithelium
Protection
Create multiple cell layers like a wall on top of each other
Sensory reception
Epithelial cell generates sensory signal
How do you classify by number of cell layers?
Simple and stratified
Simple
Each cell is attached to basement membrane
Stratified
Multiple layers; only the basal layer is directly attached to basement membrane
How do you classify by shape?
Squamous, cuboidal, columnar
Where is simple squamous? (1)
No surface projections (cilia, microvilli) in lining of air sacs in lungs (alveoli)
Where is simple squamous? (2)
Endothelium (inner lining of heart and blood cells)
Where is simple squamous? (3)
Glomerular capsule in kidney (where filtration occurs)
Where is simple squamous? (4)
Mesothelium (lining of closed body cavities)
Where is simple cuboidal?
In (most) glands and kidney tubules (provides more room for organelles)
Where is simple columnar? (1)
Non-ciliated (lines most of digestive tract)
What does the columnar shape do?
Provides more room for orangelles
What do goblet cells do?
Secrete mucus in digestive and respiratory tracts
Where is simple columnar? (2)
Lines small bronchi (air tubes in lungs) and sweeps away debris
Where is simple columnar? (3)
Lines uterine tube
Is pseudostratified actually stratified?
No, all cells are attached to basement membrane
