Chapter 4 - Skin and Body Membranes PowerPoint

Chapter 4: Skin and Body Membranes

Body Membranes

• Functions: Cover body surfaces, line body cavities, protect organs.

• Classification: Based on tissue types.

Types of Body Membranes

1. Epithelial Membranes

• Simple organs with epithelial and connective tissue layers.

2. Connective Tissue Membranes

• Include synovial membranes.

Epithelial Membranes

Cutaneous Membrane

• Skin; dry, protective boundary.

• Consists of:

  • Epidermis: Keratinized stratified squamous epithelium.

  • Dermis: Dense connective tissue.

Mucous Membranes (Mucosae)

• Moist membranes that line cavities opening to the exterior.

• Secretes lubricating mucus; adapted for absorption and secretion.

Serous Membranes (Serosae)

• Line closed body cavities, occur in pairs (visceral & parietal), separated by serous fluid.

Specific Serous Membranes

• Peritoneum: Covers abdominal organs.

• Pleurae: Surrounds lungs.

• Pericardium: Surrounds heart.

Connective Tissue Membranes

• Synovial Membranes: Loose areolar tissue lining joint cavities, secretes lubricating fluid.

Integumentary System

• Consists of skin and skin appendages (sweat oil glands, hair, nails).

Functions of the Integumentary System

• Insulates and cushions organs, protects against damage (mechanical, chemical, thermal, UV radiation, microbes).

• Regulates heat loss and acts as a mini-excretory system. Synthesizes vitamin D.

Structure of the Skin

• Composed of:

  • Epidermis: Outer layer of stratified squamous epithelium.

  • Dermis: Connective tissue underlying the epidermis, consists of papillary and reticular areas.

  • Hypodermis: Anchors skin, mostly adipose tissue, not technically part of the integumentary system.

Epidermis Layers

• Stratum basale, spinosum, granulosum, lucidum (only in thick skin), and corneum.

Skin Color

• Determined by:

  • Melanin: Ranges from yellow to black.

  • Carotene: Orange-yellow.

  • Hemoglobin: Red coloring from blood.

Appendages of the Skin

• Include sebaceous glands, sweat glands, hair, and nails.

Homeostatic Imbalances of Skin

• Infections: Athlete’s foot, cold sores, dermatitis.

• Burns: Categorized by severity (first to fourth degree).

• Skin Cancer: Most common is basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.

Developmental Aspects

• Changes in skin quality and function throughout life; affects due to aging and environmental factors.