4.1 & 4.2 Body Membranes & Skin OBJECTIVES: 1. Learn the 3 Types of Epithelial Membranes 2. How the Connective Tissue Membrane is differs. 3. Components of the Integumentary System 4. What factors effect skin color

Epithelial Membranes  3 Types  Cutaneous  Mucous  Serous

Cutaneous Membrane  SKIN!  Exposed to air and is a dry membrane

Mucous Membrane  Lines all body cavities that open to the exterior.  They are wet/moist membranes that are almost continuously bathed in secretions.

Serous Membrane  Lines body cavities that are closed to the exterior.  Occur in pairs (Visceral & Parietal)

Visceral & Parietal?  Visceral Serosa: The covering that touches the organ.  Parietal Serosa: The outer covering that does NOT touch the organ  The 2 layers are separated by a clear fluid called serous fluid.

The prefix “Peri-”…  Means “to cover”  Ex: Peritoneum: Covers organs of the abdominal cavity. Pericardium: Covers the heart (exc.) Pleura: Covers the lungs

Connective Tissue Membranes  Synovial Membrane  Composed of connective tissue  Contain NO epithelial cells  Found surrounding your joints  Provide a smooth surface and secrete lubricating fluid

Integumentary System  Made up of skin and its components such as sweat, oil, glands, hair, & nails.

Functions of the Integumentary System  Protection  Regulate Body Temperature  Insulates & Cushions  Makes Vitamin D  Prevents Water Loss

Structure of Integumentary System  2 Types of tissues:  Stratified Squamous (epidermis)  Dense Connective Tissue (dermis)  Blister: Forms when the epidermis and dermis separate from each other.  Subcutaneous Tissue: Adipose tissue deep to the dermis. Serve as a shock absorber & insulates deeper tissue.

Formation of a Blister

Epidermis  Avascular (Men can shave skin layers daily and not bleed!)  5 Layers (Deep  Superficial) 1. Stratum germinativum 2. Stratum spinosum 3. Stratum granulosum 4. Stratum lucidum 5. Stratum corneum (Thickest layer)

Layers of the Epidermis  “Good Students Graduate Less Cocky”

Epidermis still…..  Melanin: Pigment which ranges in color from yellow to brown to black.  Produced by cells called melanocytes.  Found in the Stratum germinativum.

Dermis  Papillary  Upper dermal region  Have dermal papillae  Fingerprints  Reticular  Deepest skin layer  Contains blood vessels, sweat & oil glands

Red face after running?  Blood vessels become engorged and move to the surface of the skin to cool off and regulate body temperature.

Skin Color  3 Pigments contribute to skin color:  Amount of Melanin: (yellow, red, brown, black…)  Amount of Carotene: (orange, yellow)  Amount of Oxygen in hemoglobin

More Skin Color…  Erythema: Blushing  Blanching: Pale Ghost (Vasorestriction)  Jaundice: Yellowing of Skin  Hematoma: Bruise