Epithelial Tissue Flashcards
Epithelial Tissue
- many cells tightly packed together ~ little to no extracellular matrix
- densely packed sheets of cells
- Many cell junctions
- Attach to basement membrane
- Avascular —no blood vessels - HAS a nerve supply
- Mitosis occurs frequently
Apical (free) surface
faces outside world
Lumen
hollow space (food , water)
Basal surface
Bottom
Basement Membrane
basal+reticular lamina ; formed by underlining epithelial + connective tissue
Simple
1 layer of cells
Pseudostratified
falsely; not every cell reaches apical surface, nucleus at different levels
Stratified
2+ rows of cells
Squamous
Flat “floor tiles”
Cuboidal
Squared
Columnar
Long columns
Transitional
Functional classification, shape changes based on function
Simple squamous function
• Filtration • Diffusion • Secretion
Simple squamous location
• Cardiovascular + Lymphatic
• Serous membranes
• Alveoli
• Kidneys
• inner eardrum
Simple cuboidal function
• Secretion • Absorption
Simple cuboidal location
• Ovary
• Eye Lens
• Eye Retina
• Kidney tubules
• Thyroid gland
• Pancreas
Simple cilliated columnar function
• Cilia —moves
mucus toward throat away from
lung; coughed up/ swallowed/spit out
• move oocytes from ovaries —> uterus