Lecture 6: Cell-Cell Interactions Flashcards
Epithelial Tissue:
- Lining and covering of organs and body cavities
- Secretory parts of organs and glands
- _______ membranes of capillaries and alveolar sacs,
- Membranes that _______ organs.
- Closely bound to one another by _______
Epithelial Tissue:
- Lining and covering of organs and body cavities
- Secretory parts of organs and glands
- Transport membranes of capillaries and alveolar sacs,
- Membranes that Lubricate organs.
- Closely bound to one another by Cell Junctions
The epithelium is named according to structure, arrangement, and shape.
Shape:
- ______-thin, flat cells
- cuboidal-cube shaped cells
- columnar-column shaped cells
Structure and arrangement:
- _____-one layer thick
- _____-multi-layered
- _____-appears stratified but isn’t
- _____-stretchable
- ciliated -has hair-like cilia
Shape:
- squamous-thin, flat cells
- cuboidal-cube shaped cells
- columnar-column shaped cells
Structure and arrangement:
- simple-one layer thick
- stratified-multi-layered
- pseudostratified-appears stratified but isn’t
- Transitional-stretchable
- ciliated -has hair-like cilia
_______ is the inside space or lining of a tubular structure, such as an artery or intestine
Lumen
________ Cells: secrete mucous that lubricates and protects endothelium. _______ ensures mucous is secreted on correct side
Goblet Cells: secrete mucous that lubricates and protects endothelium. Polarization ensures mucous is secreted on correct side
_________Junctions (aka Occluding junctions):
- Located beneath the luminal surface at the _____ end of simple columnar epithelia
- Occludin proteins stitch neighboring cells together
- Seals the intercellular spaces so lumenal contents cannot penetrate between cells
- Forms a continuous circumferential band or _____ around the cell
Tight Junctions (aka Occluding junctions):
- Located beneath the luminal surface at the Apical end of simple columnar epithelia
- Occludin proteins stitch neighboring cells together
- Seals the intercellular spaces so lumenal contents cannot penetrate between cells
- Forms a continuous circumferential band or Zonule around the cell
___________: Joins an actin bundle in one cell to a similar bundle in a neighboring cell
- ______ dimers are transmembrane adhesion proteins that stick to adjacent cell
- Linker proteins attach to actin within cell
Adherens Junction: joins actin bundle in one cell to a similar bundle in a neighboring cell
- CADHERIN dimers stick to an adjacent cell
- Linker proteins attach to actin within the cell
Invagination of epithelial sheet is caused by tightening along _______ in selected regions
Adhesion Belt (Attached to actin)
__________:
- Prominent cell adhesion molecule of epithelial cells
- The greater the levels in cancerous cells the less metastatic potential
E-Cadherin
____________:
- Rivet cells together
- Adhesive junctions found in a variety of tissues
- Contain ______\_ that link two cells across the narrow gap
- Link _______\_ filaments from one cell with those of the adjacent cell
- Numerous in tissue are subject to mechanical stress.
- Examples?
Desmosomes:
- Rivets cells together
- Adhesive junctions found in a variety of tissues
- Contain CADHERINS that link two cells across the narrow gap
- Link INTERMEDIATE filaments from one cell with those of the adjacent cell
- Numerous in tissue are subject to mechanical stress.
- Common in Cardiac Muscle and Epithelial layers of skin
_________: very strong linkage, stronger than the velcro-like attachment of adherins
- Have different domain structure from that in adherens junctions
- Desmoglein & desmocollin
Cadherins
Common intermediate filament of the epithelium?
Keratin
Common intermediate filament of muscle cells?
Desmin
Autoimmune disorder in which anti-desmoglein antibodies breakdown desmosomes
Pemphigus Vulgaris
__________: Sites between animal cells specialized for intercellular communication
- pores permitting passage of small molecules between cells
- Inorganic Ions
- Small water-soluble molecules
- Provide a means of electrical coupling of visceral and cardiac muscle cells permitting synchronous contraction
GAP Junctions
Gap Junctions are composed of integral membrane protein: _______
These proteins cluster within the plasma membrane as a multisubunit complex: _______
These are sensitive to ____ and close when exposed to increased levels
Gap Junctions are composed of integral membrane protein: Connexin
Connexins cluster within the plasma membrane as a multisubunit complex: Connexon
These are sensitive to Calcium and close when exposed to increased levels
