Epithelial Tissue and Glandular Epithelium

Epithelial tissue

Covers all surfaces exposed to the outside of our bodies

Endothelium

Type of epithelium that covers hollow organs, blood vessels, and body cavities

Basement membrane

Formed by basal lamina and reticular lamina

Regeneration

Rapid replacement of dead or damaged cells

Polarity

Presence of basal (near basement membrane) and apical surfaces

Squamous

Flat and thin cell shape, found in kidney tubules, alveoli of lungs, and capillaries

Cuboidal

Boxy cell shape, active in secretion and absorption

Columnar

Taller than wide cell shape, good for secretion

Pseudostratified

Irregular shaped cell type that appears stratified but is simple

Transitional epithelium

Found in the urinary tract, with apical cells transitioning from cuboidal to squamous as the bladder fills with urine

Endocrine gland

Ductless gland that secretes into surrounding tissue or fluid, used for hormones

Exocrine gland

Gland with a duct that opens to the external environment, secreting substances like mucous, saliva, sweat, and breast milk

Eccrine secretion

Type of secretion where vesicles move toward the cell membrane, common in sweat glands

Apocrine secretion

Secretory content is pinched off and ducts to hair follicles, producing odor, common in areas like the armpits

Holocrine secretion

Secretion type involving eruption and destruction of gland cells, producing oils on skin and hair

Serous Gland

Gland producing watery, blood-like secretions rich in enzymes, acting as a lubricant

Mucous gland

Gland producing watery to viscous fluid rich in glycoprotein mucin, found in digestive, respiratory, urinary, and reproductive systems

Ceruminous Gland

Gland found only in the external ear canal