Unit 1: Epithelial Tissue - Terms and Info

Epithelium

Avascular tissue composed of cells that cover body surfaces, closed cavities, and tubes.

Characteristics of the Epithelium

they are closely apposed and attached to one another, they have distinct surfaces (Lateral, Apical, and Basal), and special basement membrane known as the basal lamina

what does simple mean in relation to the epithelium?

made of one layer of cells

what does stratified mean in relation to the epithelium?

Multiple layers of cells

what does squamous mean in relation to the cells?

wider than tall, appearing flattened

what does Cuboidal mean in relation to the cells?

same dimensions in width and height

what does Columnar mean in relation to the cells?

taller than wide, appearing stretched high

what does transitional mean for the cells?

special classification describing cells that look different by layer. This can be seen in the bladder, and appearances change based on fullness of bladder.

what does Pseudostratified mean for the cells?

special classification that describes a layer of cells that looks stratified, but is simple in reality.

what is Mesothelium?

simple epithelium lining the closed body cavities

what is Endothelium?

epithelium that lines blood vessels

what are Glands?

specialized epithelium that is responsible for secretion

what are found on the apical surface of epithelial cells?

cilia (motile) or microvilli (non-motile)

what is found on lateral surfaces of epithelial cells?

Gap junctions, Desmosomes, Zonula adherens, and Zonula occludens

what is found on basal surface of epithelial cells?

Hemidesmosomes attaching to basal lamina

what is a goblet cell?

unicellular gland

what does Merocrine mean for a gland?

mode of secretion in which vesicles deliver secretion to plasma membrane

what does Apocrine mean?

mode of secretion in which entire apical area of cell is lost with secretion

what does Holocrine mean?

mode of secretion in which whole cell becomes the secretion

what does serous mean for secretion?

it is a watery substance

what does mucous mean for secretion?

it is a viscous substance