Chapter 5: Tissue Organization Flashcards
What are the characteristics of epithelial tissue?
1 or more layers of closely packed cells with minimal extracellular matrix
Where is epithelial tissue found?
- covering body surfaces
- lining cavities
- forming glands
What are the 2 surface of epithelium?
- apical surface: superficial; exposed to external environment / internal body space
- basal surface: deep; epithelium is attached to basement membrane
Is epithelial tissue vascular or avascular?
avascular - nutrients are obtained across apical surface or via diffusion
Is epithelial tissue innervated or not?
extensive innervation to detect environmental changes
What are the main functions of epithelial tissue?
- physical protection
- selective permeability
- Secretions
- Sensations
What are the classification of epithelial cell layers?
- simple (1 layer of cells)
- Stratified (2+ layers of cells)
- Pseudostratified (appears layered due to nuclei)
What are the classification of epithelial cell shape?
- squamous
- cuboidal
- columnar
- transitional
Where is simple squamous epithelium found?
- alveoli
- lining blood vessels
- serous membranes
*thinnest barrier, allows rapid movement of molecules across surface
Where is simple cuboidal epithelium found?
- kidney tubules
- surface of ovary
*designed for absorption and secretion
Where is non-ciliated simple columnar epithelium found?
-inner lining of digestive tract
Where is ciliated simple columnar epithelium found?
-lining of larger bronchioles in lungs, uterus
Where is stratified epithelium found?
- skin
- lining of esophagus
- lining of bladder
*able to resist wear and tear
Where is non-ciliated pseudostratified columnar epithelium found?
-urethra, epididymis
Where is keratinized stratified squamous epithelium found?
the epidermis
Where is non-keratinized stratified squamous epithelium found?
- oral cavity
- parts of pharynx
- esophagus
- vagina
- anus
Where is stratified cuboidal epithelium found?
- sweat glands
- male urethra
- ovarian follicles
Where is stratified columnar epithelium found?
-large ducts of salivary glands
What are the 3 main types of glands?
- Merocrine
- Apocrine
3 Holocrine
What is a merocrine gland?
- packages secretions into vesicles and release them via exocytosis
- lacrimal, salivary, sweat, pancreas, stomach
What is an apocrine gland?
- apical membrane pinches off secretions, thus damaging the cell and requiring repair
- mammary, ceruminous
What is a holocrine gland?
- cell accumulates something, then dissolves itself, and the final product is a viscous mixture of the 2
- sebaceous glands
What is the most diverse, abundant, and widely distributed of the tissues?
connective tissue
All connective tissue share what common origin?
embryonic mesenchyme
