Page 143 - Atlas of Histology with Functional Correlations

Simple Columnar Epithelium

All cells are tall, some lined by microvilli
Lines the lumina of digestive organs
Secretes protective mucus for stomach lining
Absorption of nutrients in small intestine

Pseudostratified Columnar Epithelium, Epithelium

with Cilia or Stereocilia

All cells reach basement membrane, but not all reach the surface
Ciliated cells interspersed among mucus-secreting goblet cells
In respiratory passages, ciliated and mucus cells clean inspired air and
transport particulate matter across cell surfaces

In uterine tubes and the efferent ducts of testes, ciliated cells transport
oocytes and sperm across cell surfaces, respectively In the epididymis and
vas deferens, the lining stereocilia absorb testicular fluid
In the inner ear, stereocilia perform sensory functions for hearing and balance

Stratified Epithelium

Formed by multiple layers of cells, the superficial cell layer determining
epithelial type

Nonkeratinized squamous epithelium contains live superficial cell layer
Nonkeratinized squamous forms moist and protective layer in esophagus,
vagina, anal canal, and oral cavity
Keratinized epithelium contains dead superficial cell layer

Keratinized epithelium provides protection against abrasion, bacterial
invasion, and desiccation
Cuboidal epithelium lines large excretory ducts in different organs
Cuboidal epithelium provides protection for the ducts

Transitional Epithelium

Found exclusively in renal calyces, renal pelvis, ureters, and bladder
Changes shape in response to distensions caused by fluid accumulation

Plaques in the cells allow extensions of the epithelium during fluid

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