Epithelial Tissue Flashcards
list the five functions of epithelial tissue
- protection of underlying tissue
- absorption
- secretion
- excretion
- sensation
what are the five characteristics of epithelial tissue?
- distinct cell surfaces
- mostly comprised of cells
- covers body surfaces, lines openings, lines inside of body, inside of heart, lungs, and cavities
- nonvascular
- capable of regeneration
what are the three types of distinct epithelial cell surfaces?
- apical (free) surfaces
- lateral surfaces
- surfaces attached to basement membranes
what are apical or free surfaces?
not attached to any other cells
what are lateral surfaces?
attached to other epithelial cells
what is the basement membrane?
attaches epithelial cells to underlying tissue, produced by epithelium and underlying tissue (usually connective)
are there a lot of extracellular components in epithelial tissue?
not really, it is mostly tightly packed cells
what are the two ways of classifying epithelial tissue?
- by arrangement of layers
2. by cell shape
list and describe the three categories of epithelial classification based on arrangement of layers?
- simple: just one layer of cells, nuclei line up
- pseudostratified: one layer of cells but LOOKS like more than one layer, all cells attached to basement membrane, different heights, always columnar
- stratified: 2 or more cell layers, nuclei stack up
list and describe the three categories of epithelial tissue based on cell shape
- squamous: very thin and plate-like
- cuboidal: square-like, all sides fairly even
- columnar: longer than they are wide
describe simple squamous epithelial tissue
thin layer, not adapted to withstand wear and tear
where is simple squamous epithelial tissue found?
lining blood vessels, the heart, parietal and visceral pleura and peritoneum, the alveoli of the lungs
where is simple cuboidal epithelial tissue found?
in renal tubules, thyroid gland, and ovary surfaces
describe the shape and list the two types of simple columnar epithelial tissue
taller than it is wide, ciliated and non ciliated
state and describe the specialized cells that are found in simple columnar epithelial tissue
goblet cells: secretes mucus for lubrication/moisture/ maintenance/protective function
what are cilia?
hair-like extensions of the apical surface, move particles along in a unidirectional manner in the oviduct and respiratory tract