Histology: Epithelia Flashcards
What is the target of colchicine?
Microtubule polymerization - prevent neutrophil migration in gout
What do vincristine and vinblastine target?
Inhibit formation of mitotic spindle formed by microtubules - used in cancer therapy
What bind the extra and intracellular domains of the integrins?
- Extracellular ▶️ fibronectin and laminin
- Intracellular ▶️ actin filaments
What do the extra and intracellular domain of cadherins bind?
- Extracellular ▶️ cadherin dimer on another cell
- Intracellular ▶️ actin filaments (catenin complex of proteins)
What cell junctions are first damaged in malignant cell invasion? Why does it occur?
- Zonula occludens and adherens
- loss of expression of cadherins ▶️ weakness the epithelium
What is the target cell junction in pemphigus vulgaris?
- autoantibodies against Desmosomal proteins in skin cells
What is the cell junction target in bollous pemphigoid?
- autoantibodies against basement membrane hemidesmosomal proteins
What is cause of infertility in kartagener syndrome? What other manifestations may have?
- immotile spermatozoa due absence of dynein
- chronic respiratory infections (similar defect of respiratory epithelium)
What defines the polarity of the epithelial cell?
The thigh junctions between them (separate apical and basolateral region)
Which molecule is essential for organelle transport?
Kinesin
In what cells can you find vimentin (intermediate filament)?
Cells of mesenchymal origin ▶️ endothelial cells, fibroblasts, chondroblasts, and vascular smooth muscle.
In what cells can you find vimentin (intermediate filament)?
Cells of mesenchymal origin ▶️ endothelial cells, fibroblasts, chondroblasts, and vascular smooth muscle.
Which junctional specializations would most likely be found between cells in the Malpighian layer of the epidermis?
Desmosomes
*They join newly formed keratinocytes in the basal layers of the epidermis and help keep cells together in epithelia under stress
A deficiency in a phosphotransferase enzyme results in mucolipidosis II (I-cell disease). Which organelle is lacking the enzyme?
Golgi apparatus
*results in hydrolases being secreted rather than being incorporated into lysosomes
Where is synthesized catalase and its location once made?
- free polysosomes
- are the site of synthesis for proteins destined for the nucleus, peroxisomes, or mitochondria
- Peroxisome
- Catalase is a major peroxisomal protein that degrades hydrogen peroxide into water and oxygen
