This membrane is a mixture of carbohydrates and proteins secreted by the epithelial and connective tissue cells. Epithelial cells may be squamous, cuboidal, or columnar in shape and may be arranged in single or multiple layers. Simple cuboidal epithelium is found in glandular tissue and in the kidney tubules.
Exocrine glands produce secretions to free surfaces, whereas endocrine glands deliver their secretions to the blood. The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
Skip to main content. This service is more advanced with JavaScript available. Advertisement Hide. Keratinized epithelium is only found on the skin stratum corneum.
The epidermis is a keratinized stratified squamous epithelium. References Standring S. Elsevier Health Sciences ; Finger-shaped, non-active motile projections on the apical surface of epithelial cells. Eyelash-shaped, active motile projections on the apical surface of epithelial cells. Inner structure composed of actin filaments Cross-linkage by fimbrin. Inner structure composed of actin filaments.
Inner structure composed of microtubules Anchored in the cytoplasm via basal bodies kinetosomes. Intestine: enterocytes Kidney : epithelium in the proximal tubule. Inner ear : hair cells of the organ of Corti hearing and the v estibular organ sense of balance Epithelium of the epididymal duct and vas deferens. Respiratory tract : respiratory epithelium Epithelium of the fallopian tubes Epithelium of efferent ducts epididymis.
No active motion possible Flexible passive motion in the inner ear Inflexible rigid in the epididymal duct and vas deferens. Active motion possible through interaction between dynein and microtubules. Increases the absorption surface area of the epithelia. A n organised collection of secretory epithelial cells. Most glands are formed during development by proliferation of epithelial cells so that they project into the underlying connective tissue.
Other glands lose this direct continuity with the surface when their ducts degenerate during development. This is the parotid gland , a type of salivary gland. Can you identify the secretory acini and the ducts in this typical exocrine gland. The intensity of staining should tell you that the secretory cells of this gland are serous. This gland secretes thin watery secretions, which are rich in enzymes and antibodies, and the ducts open onto surface of oral mucosa.
Exocrine glands have ducts - and they secrete onto a surface: examples of exocrine glands are: sebaceous and sweat glands in the skin , salivary glands oral , Brunner's glands.
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