Body membrane

Body membrane

Formed from epithelial layer bound to underlying CT

Line body cavities

Cover viscera

Cover body's external surface

Four types:

Mucous

Serous

Cutaneous

Synovial

Mucous membrane

Mucosa

Lines compartments that open to external environment Includes: digestive, respiratory, urinary, and reproductive tracts

Performs absorptive, protective, and secretory functions

Formed from epithelium and underlying CT

CT component, lamina propria

Covered with a layer of mucus derived from goblet cells, multicellular glands, or both

Serous membrane

Lines body cavities that do not open to external environment

Simple squamous epithelium (mesothelium)

Produces thin, watery serous fluid

Derived from blood plasma

Reduces friction between opposing surfaces

Forms parietal and visceral layers

Serous cavity is in between

Cutaneous membrane

Skin

Covers external surface of body

Composed of

Keratinized stratified squamous epithelium

Underlying CT

Protects internal organs and prevents water loss

Synovial membrane

Lines some joints in body

Composed of

Areolar CT

Covered by squamous epithelial cells lacking basement membrane

Synovial fluid secreted by epithelial cells

Reduces friction among moving bone parts

Distributes nutrients to cartilage