Epithelial Tissues and Glandular Epithelium (Lecture Video Notes)

Vocabulary flashcards covering key epithelial tissue types, their locations, structures (basement membrane, apical/basal surfaces), and related concepts (glands, Pap smear, dysplasia, transitional epithelium, keratinization, goblet cells, microvilli, and cilia) as discussed in the lecture notes.

Simple squamous epithelium

A single layer of flat, thin cells optimized for rapid absorption/secretion and reduced friction; lines heart and blood vessels (endothelium) and lines lung air sacs and body cavities (mesothelium).

Endothelium

Simple squamous epithelium that lines the heart and blood vessels.

Mesothelium

Simple squamous epithelium lining the thoracic and abdominal cavities.

Simple cuboidal epithelium

One-cell-thick layer of cube-shaped cells; found in ovaries (follicles), kidneys tubules, and lining ducts of glands (e.g., thyroid, pancreas); functions in secretion and absorption.

Simple columnar epithelium

One-layer tall, column-shaped cells; nucleus near the bottom; lines the digestive tract from stomach to anus; functions in secretion and absorption; may have goblet cells and microvilli or cilia.

Goblet cells

Specialized epithelial cells that secrete mucus onto the surface to lubricate and protect mucous membranes, common in GI and respiratory tracts.

Microvilli

Small, finger-like projections on the apical surface that increase surface area for absorption; resemble peach fuzz.

Cilia

Long, hair-like projections on the apical surface that move mucus and trapped material out of the respiratory tract.

Pseudostratified ciliated columnar epithelium

Appears multi-layered due to nuclei at different levels but is a single layer; often has cilia; found in the upper respiratory tract; traps and moves mucus.

Stratified squamous epithelium

Two or more layers of cells; provides protection in high-wear areas; can be keratinized or non-keratinized.

Keratinized stratified squamous epithelium

Stratified squamous epithelium with keratin in the top layers (dead cells); seen in skin; provides toughness and water resistance.

Non-keratinized stratified squamous epithelium

Moist stratified squamous epithelium without keratin; lines mouth, esophagus, vagina, anus, and pharynx.

Stratum corneum

Outermost layer of dead, keratin-filled cells of the epidermis.

Pap smear

Cervical cytology test that scrapes epithelial cells from the cervix to screen for cervical cancer and dysplasia, often related to HPV.

Dysplasia

Precancerous changes in epithelial cells; may progress to cancer if not monitored or treated.

Transitional epithelium

Also called urothelium; found in urinary tract (bladder and ureters); highly stretchable; appearance changes from cuboidal when empty to flattened when stretched.

Urothelium

Another name for transitional epithelium of the urinary tract.

Glandular epithelium

Epithelial tissue that forms glands and secretes substances; includes endocrine and exocrine glands.

Endocrine gland

Gland that secretes hormones directly into the bloodstream.

Exocrine gland

Gland that secretes substances into ducts or onto body surfaces (e.g., sweat glands, sebaceous glands).

Sweat gland

An exocrine gland that secretes sweat onto the skin surface via ducts.

Thyroid gland

An endocrine gland that stores thyroid hormones; essential for metabolism; contains cells that store hormones in the gland.

Basement membrane

Thin layer that anchors epithelium to underlying connective tissue; separates epithelium from the dermis and provides support.

Avascular

Epithelial tissue lacks its own blood vessels and relies on underlying connective tissue for nutrients and oxygen.

Dermis

Connective tissue layer beneath the epidermis containing blood vessels, nerves, and other structures; provides nourishment to epithelium.