Epithelial membranes Flashcards
Epithelial membranes
Membranes are flat sheets of tissue that cover or line a part of the body.
An epithelial membrane consists of an epithelial tissue bound to an underlying connective tissue layer. (In other words, it is the epithelial tissue and connective tissue together that compose the epithelial membrane.)
3 types of epithelial membranes
1) Cutaneous Membranes
2) Mucous Membranes
3) Serous Membranes
Cutaneous Membrane
also known as skin; dry membrane; covers the external surface of the body; consists of epidermis (keratinized stratified squamous epithelium) and dermis [loose (areolar) connective tissue and dense irregular connective tissue].
Mucous Membrane
also known as mucosa; wet membrane; lines a body cavity that opens directly to the exterior; find lining all of the digestive, respiratory, and reproductive tracts, as well as much of the urinary tract; consist of lining epithelium and an underlying layer of connective tissue called the lamina propria; this underlying connective tissue is loose (areolar) connective tissue; often there are goblet cells and other types of epithelial cells that secrete mucous to prevent cavities from drying out. Mucous can also protect (stomach from acid), collect dust particles.
Serous Membranes
Serous Membranes – also called serosa; wet membrane; lines body cavities that do NOT open directly to the exterior and the organs that lie within that cavity; consists of mesothelium (simple squamous epithelium) with underlying loose (areolar) connective tissue. Organs within the ventral body cavity (these organs called viscera) and the walls of the cavity are covered with a serous membrane.
Can be named for what it lines or covers - visceral/parietal
Parietal layer
parietal layer – lines the walls of the cavity
Visceral layer
2) visceral layer – adheres to the surface of the organ
serous fluid
located between the parietal and visceral layers to reduce friction when the viscera move.
Serous membranes consist of
mesothelium (simple squamous epithelium) with underlying loose (areolar) connective tissue.
Serosa - do not line cavities that open to exterior.
Lamina propria
Connective tissue of mucous membrane.
Like a hand in a balloon
Serous membranes - all one membrane, but there is the outer rubber outside of organ and it reflects back.