Chapter 3: Membranes and the Integumentary System Lesson 3.1 Body Membranes

Body Membranes Body membranes surround and help protect the body’s surfaces. Epithelial membranes mucous membranes serous membranes cutaneous membranes Connective tissue membranes synovial membranes

Epithelial Membranes Mucous membranes Line cavities open to the environment These cavities include all the hollow organs of the respiratory, digestive, urinary, and reproductive tracts. The mucous membranes are all moist Mucus is a slippery solution that protects the mucous membranes and aids in transporting substances.

Epithelial Membranes Serous membranes Line cavities not open to environment These include: the pleura, which encloses the lungs; the pericardium, which surrounds the heart; the peritoneum, which lines the abdominal cavity. Each serous membrane forms a double lining with an outer lining and an inner lining. The outer lining of each body cavity is called the parietal layer. The inner lining that covers each organ within a body cavity is called the visceral layer.

Epithelial Membranes Serous membranes secrete a thin, clear fluid called serous fluid which serves as a lubricant between the parietal and visceral membranes to minimize friction and “wear and tear”

Mucous Membranes and Serous Membranes

Epithelial Membranes Cutaneous membranes Forms what we know as skin The basic structure of skin is a keratinizing, stratified (layered) squamous epithelium over dense, fibrous connective tissue. Although the skin contains sweat glands, it is a dry membrane when sweat is not present.

Connective Tissue Membranes Synovial membrane Is the only type of membrane in the body that is composed solely of connective tissue and includes no epithelial cells. lines the capsules that surround synovial joints, such as the shoulder and knee. Surrounds tendon sheath Secretes synovial fluid which provides cushioning and reduces friction.

Assignment is due at the end of class Write in complete sentences

The Integumentary System Chapter 3: Membranes and the Integumentary System Lesson 3.2 The Integumentary System

Functions of the Integumentary System The skin (cutaneous membrane) forms a protective cover against abrasion chemical damage drying out UV radiation damage The skin’s outermost layer contains keratin, a tough protein also found in hair and nails that adds structural strength.

Functions of the Integumentary System Regulates body temperature due to the extensive array of tiny capillaries and sweat glands that lie near the surface of the skin. When the body is overheated, the capillaries dilate, enabling body heat to dissipate. When the environment is cold, the capillaries constrict, and blood flow moves to deeper vessels away from the skin to minimize heat loss.

Functions of the Integumentary System

Anatomy of the Skin The skin has two layers an outer epidermis an underlying dermis The epidermis and dermis are thick over areas such as the soles of the feet and thin in delicate areas such as the eyelids. Beneath the dermis is the hypodermis, or subcutaneous fascia, which serves as a storage repository for fat. A blister is produced when a burn or friction causes these two layers to separate, forming a fl uid-fi lled pocket.

Anatomy of the Skin The hypodermis is not part of the skin, but it connects the skin to the underlying tissues. It also provides cushioning and insulation against extreme external temperatures.

Anatomy of the Skin Epidermis Dermis Hypodermis

Layers of the Epidermis Is the outer layer of skin that we see. It contains five layers of tissue: from superficial to deep (the outside going in), stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale All epidermal layers consist of cells, with no blood supply to provide nutrients to the skin.

Put together skin foldable The Skin Foldable Color Code A – Orange B – Blue C – Green D – Purple E - Yellow