Epithelium Flashcards
What are the two sections of epithelial cell basement membrane?
basal lamina reticular lamina
What type of collagen is the basal lamina comprised of?
type four
What type of collagen is the reticular lamina comprised of?
type three
What type of stain is used to highlight the basement membrane? What type of molecule does it stain?
PAS stain – stains glycoproteins
Where is simple squamous epithelium found in the body?
Lining of vascular system (blood/lymph) Lining of body cavities Lining of respiratory spaces in the lung Lining of Bowman’s capsule in the kidney
Where is stratified Squamous epithelium found in the body?
Epidermis Lining of oral cavity/esophagus Lining of the vagina
Where is simple cuboidal epithelium found in the body?
Small ducts of exocrine glands Kidney tubules Ovary “germinal” epithelium (on outside of ovary)
Where is simple columnar epithelium found in the body?
Primarily GI tract Small intestine and colon lining gallbladder lining stomach lining and gastric glands “often contain microvilli”
Where is pseudostratified columnar epithelium found in the body?
Trachea and bronchi lining Male reproductive tract “often is ciliated, which helps to trap and move things like mucus”
Where is stratified cuboidal found?
Primarily large ducts Sweat gland ducts large ducts of exocrine glands like salivary glands
Where are stratified columnar found?
Largest exocrine glands (salivary, tear ducts)
Where is transitional epithelium located?
Only lining urinary passages!! (Urothelium)
What is the difference between exocrine and endocrine glands?
Exocrine - Secrete products onto surface via ducts Endocrine - NO DUCTS - secrete into connective tissue spaces where they are absorbed into bloodstream by capillaries.
Mucus secretion vs serous secretions
Mucus: appears translucent in H and E stains, protects and lubricates cell surfaces Serous: appears slightly darker in H and E, watery secretions often rich in enzymes.
What are the three mechanisms of secretion? (Merocrine, Apocrine, Holocrine)
Merocrine: cells release their contents by exocytosis (ex parotid salivary gland, most glads are this type) Apocrine: part of the secretory cell apical cytoplasm is released along with the contents. Holocrine: entire secretory cell and its contents released (ex sebaceous gland)
