Part 1- Epithelium Flashcards
Cells are polarized and avascular attached by special cell to cell junctions and to underlying connective tissue
Epithelium
All three germ layers give rise to
Epithelium
One layer of cells with all cells attached to the basal lamina
Simple Epithelium
More than one layer with only the basal cells attached to the basal lamina
Stratified epithelium
Most common epithelium which functions in ion or gas exchange, diffusion, and filtration
Simple squamous epithelium
Epithelium found in glands, gland ducts, bronchioles and nephrons functions in secretion or absorption
Simple cuboidal
Epithelium found in stomach, intestines, gall bladder, female reproductive system, bronchioles and function in secretion and absorption
Simple columnar
Epithelium found in respiratory system and male reproductive system
Pseudostratified epithelium
Epithelium lining all areas continuous with epidermis ie lining of oral cavity, esophagus, anal canal, vagina, cornea and functions in protection from abrasion and irritation in moist locations.
Stratified squamous nonkeratinized
Epithelium lining the epidermis of the skin and hard palate functions in protection from abrasion and irritation
Stratified squamous keratinized
Epithelium lining the urinary system, functions in protection from urine
Transitional epithelium
Areas changing from stratified type to simple
Stratified columnar or cuboidal
Specialized extracellular fibrous sheet that attaches epithelial cells to connective tissue. _________ is a term used to describe the sheet when it is thick enough to be visible under light microscope.
Basal lamina, Basoment membrane
Epithelial cells must be attached to the _______ to maintain normal function
Basal Lamina
A layer made of Type IV collagen which is always present and secreted by epithelial cells.
Basal Lamina
A layer which primarily contains Type III collagen fibrils continuous with the ECM of the connective tissue.
Reticular Lamina
Alternate terms for microvilli
Striated border (small intestines) Brush border (kidney nephron) Stereocilia (male reproductive system)
Stiff brush like structures composed of actin filaments
Microvilli
Motile finger like structures composed of microtubules in a 9+2 doublet arrangement in the axoneme and 9 triplets in the basal body
Cilia
Area of complete fusion between adjacent cell membranes. Functions to completely black passage of molecules between cells. Basis of blood tissue barriers.
Tight junction
Zonula occludens
Dense area with actin filaments that completely encircles cell. Functions to anchor actin filaments to cell membrane. Stabilizes cytoskeleton.
Intermediate junction
Zonula adherens
Keeps neighboring cells from pulling apart, strong cells to ell attachment.
Desmosomes
Macula adherens
Attaches cell to basal lamina
Hemidesmosome
Neighboring cell membranes form small channels or bridges between cells that permits movement of small molecules between cells.
Gap junction
Communicating nexus junction
Epithelial cells specialized for secretion
Glandular epithelia
Cells specialized to secrete onto an epithelial surface (free or apical surface)
Exocrine cells
Cells specialized to secrete a product (hormone) into connective tissue where it enters capillaries.
Endocrine gland
How do exocrine glands develop?
As down growths from surface epithelium
Secretory vesicles discharge with little or no loss of apical cytoplasm
Merocrine (Eccrine)
Secretory vesicles discharge with loss of some apical cytoplasm present in mammary, sweat, and anal glands.
Apocrine
Secretory vesicles discharge with the whole cell explodes or disintegrates present in sebaceous glands
Holocrine
Single duct
Simple gland
Gland with more than one duct, and many branches
Compound gland
Gland that secretes a watery, protein rich secretion. In the GI system, contain digestive enzymes.
Serious cells
Glands that secrete slimy, viscous, lubricating glycoproteins
Mucous cells
Basophilic cytoplasm with secretory granules and a visible nucleolus
Serous cell
Light or empty appearing cytoplasm with a dark nucleus flattened at base of cell
Mucous cell
Common type of mucous cell shaped like a water goblet typically identified as a space or bubble
Goblet cell
Mixed gland with both serous and mucous cells usually contain a serous cell surround mucous called a “demilune”.
Seromucous glands
The replacement of one fully differentiated cell type for another due to some stressful stimulus. Can be reversible if the stimulus is removed.
Metaplasia
Abnormal maturation of the tissue, exhibited by alterations in size and shape of the cells and overall architecture of the tissue. Although possibly reversible, considered precancerous.
Dysplasia
New uncontrolled proliferation of cells that can be classified as benign or malignant
Neoplasm
3 features that classify a neoplasm as benign or malignant
1) degree of fidelity to precursor cells
2) rate of growth
3) ability to metastasize
Localized growth that do not penetrate adjacent tissue borders, or metastasize to distant sites. As a rule, usually differentiated cells similar to their parents.
Benign tumors
Neoplasms that have the ability to invade nearby tissues and metastasize to distant sites
Malignant neoplasms
Neoplasm derived from embryonic tissue of all 3 germ layers
Teratomas
Malignant neoplasms derived from mesenchyme, the embryonic CT
Sarcomas
Suffix of benign vs malignant neoplasms
“-oma” “-sarcoma”
Name benign and malignant name for neoplasm of the epithelium
Epithelioma, carcinoma
Name benign and malignant name for neoplasm of the glandular epithelium
Adenoma, adenocarcinoma
Name benign and malignant name for neoplasm of connective tissue
Fibromas, fibrosarcoma
Name benign and malignant name for neoplasm of cartilage
Chondroma, chondrosarcoma
Name benign and malignant name for neoplasm of bone
Osteoma, osteosarcoma
If the abnormal cancer cells are restricted to the epithelium and are an above intact basal lamina, it is classified as
Carcinoma in situ
The malignant cells attach to the basal lamina, secrete collagenases and other protease that dissolve the membrane, and invade the connective tissue, where they can break into blood or lymphatic vessels. Using these vessels, they can reach distant sites.
Metastasis
Name benign and malignant name for neoplasm of glia in adult CNS
Glio, glioblastoma
Microvilli and cilia May be present on what type of epithelium
Simple columnar, simple cuboidal, pseudostratified
