Lecture 2 - Epithelial Cells Flashcards
Do epithelial cells have blood supply?
No
What Is the Basal Lamina?
Lamina Lucida
Lamina Densa
What is the basement membrane?
Lamina Densa
Reticular Fibers
Includes Anchoring Fibril (Type VII Collagen)
Type IV collagen is made by ______.
Epithelial Cells
Type III and VII collagen are made by ______.
Connective Tissue Cells
Tight Junction Protein and Function
- Claudin
2. Helps seal the cell, preventing water loss as well as the passage of substances in between the cells
Adherent Junction Protein
Cadherin (interacts in precence of Ca2+) + Catenin + acting-binding protein + actin fillament
Adherent Junction Shape and function
Surrounds the Cell, stability, and help seal the tight junction
Desmosome Protein
Cadherin + Desmoplakin/Plakoglobin + Intermediate filament
Desmosome Shape and Function
Does not encircle, goes through the cell, anchors to intermediate filaments, provides stability to the cell
Gap Junction Protein
Connexin
Forms hydrophilic pore
Hemidesmosome Protein
Integrin
Microvilli Structure
Microfilaments go up into microvilli to give support
- Made of actin + connecting fibers
Stereocilia
Longer than microvilli
branched
function of stereocilia
facilitate absorption
Cilia shape
Longer/wider than microvili
cilia function
movement
glandular epithelia orgin
from epithelial layer during fetal development
glandular epithelia function
secretion
goblet cell formation
During fetal development, goblet cells differentiate from epithelial cells
Goblet cell function
secrete mucous for intestine and respiratory tracts
Goblet cells, single or multicellular gland?
single
Endocrine vs Exocrine
Endocrine does not have ducts
Exocrine has ducts
Formation of endo/exocrine glands
During fetal development there is a proliferation and differentiation of epithelial cells into ductal and secretory epithelial cells
Do not break BL/BM
Different Types of Exocrine Gland Structural classifications (simple x4)
- Tubular
- Branched Tubular
- Acinar
- Branched Acinar
Different Types of Exocrine Gland Structural classifications (compound x3)
- Tubular
- Acinar
- Tubuloacinar
Different Types of exocrine glands (x3)
Merocrine
Holocrine
Apocrine
Merocrine Secretion
Most Exocrine Glands
Most proteins do not diffuse across the membrane –> use exocytosis
Apocrine Secretion
Apical membrane w/ cytoplasm and lipid droplet pinches off
-can produce large quantities –> mammary gland
Holocrine Gland
aka sebaceous glands
cells disintegrate and everything goes into ducts
-think “pimple”
Synonym for tight junctions
Zonulae Occuldens
Synonym for adherent junctions
Zonula Adherens
Synonym for desmosome
Macula Adherens
