Epithelial Tissue Flashcards
Where is epithelia found?
- covers body surfaces
- lines body cavities
- forms glands
Epithelial cells are characterized but he production of ______ intermediate filaments.
Keratin
Do different epithelia produce the same keratin?
No - different epithelia produce different keratin
What is the purpose of different epithelia producing different keratin?
Useful in tumor ID
What is epithelia derived from?
Ectoderm
Endoderm
Mesoderm
What does the ectoderm give rise to?
- epidermis (hair,nails,glands, mammary glands); oral and anal mucosa
- cornea and kens epithelia of eye
- enamel organ and enamel of teeth
- anterior pituitary (adenohypophysis)
- inner ear
What does the neuroectoderm give rise to?
-neural tube (—> CNS)
Pineal body, posterior pituitary (neurohypophysis), sensory epithelium of eye, ear and nose
-neural crest (-> PNS)
Ganglia, nerves, glial cells, adrenal medulla, melanocytes, neuroendocrine cells
What does the mesoderm give rise to?
Epithelial if kidneys and gonads
- mesothelioma (lining pleura, peritoneal, and pericardial cavities)
- endothelium (blood and lymph vessels)
- adrenal cortex
What does the endodermis give rise to?
- respiratory epithelium
- alimentary epithelium (except oral and anal cavity)
- Liver, pancreas, gallbladder, thyroid, parathyroid, and thymus
- epithelial lining of tympanic cavity and Eustachian tubes
- transitional epithelium of bladder
What are the functions of epithelia?
- barrier (skin)
- SPM
- secretion (stomach)
- absorption (intestines)
- transport (cilia in trachea)
- sensation (taste buds)
Is epithelia a vascular penetrated by blood vessels?
No never
What is epithelia avascular supported by?
Basement membrane
What does the epithelia avascular separate?
Epithelium from underlying connective tissue and blood vessels
Cells of epithelium rely on ______ of O2 and nutrients from underlying tissue
Diffusion
Epithelium that lines cavities that connect with outside world:
Mucous membranes (mucosa)
