CHAPTER 4SKIN and BODY MEMBRANES

BODY MEMBRANES Defined as the outermost edge, where

tissue interacts with the environment. Environment could be the atmosphere,

ingested food or a body cavity.

BODY MEMBRANES (functions) cover surfaces -line body cavities -form protective sheets around organs - often lubricate organs

BODY MEMBRANES 2 TYPES OF BODY MEMBRANES

(described by tissue make up)

1. EPITHELIAL MEMBRANES 2. CONNECTIVE TISSUE

MEMBRANES

EPITHELIAL MEMBRANES (3)1. CUTANEOUS MEMBRANE- location- SKIN-

Characteristics-Superficial EPIDERMIS is composed of a keratinized stratified squamous epithelium.

Underlying DERMIS is composed of dense (fibrous) connective tissue.

THIS IS THE ONLY DRY EPITHELIAL MEMBRANE.

EPITHELIAL MEMBRANES (3)2. MUCOUS MEMBRANES- (mucosa)-location- This

membrane lines all the body cavities that are open to the exterior. (respiratory, digestive, urinary)

Characteristics- various epithelium (simple squamous, cuboidal, columnar) resting on LAMINA PROPRIA which is some a loose connective tissue.

Epithelium of mucosae is adapted for absorption or secretion. Most secrete mucus (except for lining of urinary tract) and are considered WET MEMBRANES.

EPITHELIAL MEMBRANES

EPITHELIAL MEMBRANES (3) 3. SEROUS MEMBRANES- (serosa)-

location – line body cavities that are closed to the exterior

Characteristics- layer of simple squamous epithelium resting on a thin layer of areolar connective tissue

Serosa produces SEROSA FLUID a clear fluid – which allows organs to slide easily across the cavity walls and other organs because they produce

SEROUS MEMBRANES

SEROUS MEMBRANES- Serous membranes occur in pairs PARIETAL LAYER – lines the walls

of the body cavities VISCERAL LAYER- covers the

organs

SEROUS MEMBRANES- IDENTIFIED BY LOCATION- PLEURA- serosa found around the

lungs PERICARDIUM- serosa around the

heart PERITONEUM- serosa around the

abdominal cavity

SEROUS MEMBRANES-QUIZ TIME1. Parietal pleura-2. Visceral pleura-3. Parietal peritoneum-4. Visceral peritoneum-5. Parietal pericardium-6. Visceral pericardium-

CONNECTIVE TISSUE MEMBRANES (1)SYNOVIAL MEMRANES- location-

synovial joints- nearly all movable joint- knee, elbow, etc

Characteristics- made of soft areolar connective tissue

Provide a smooth surface and secrete lubricating synovial fluids

SYNOVIAL MEMBRANE

SYNOVIAL MEMBRANE