Mrs. Cobb C.4 Integumentary System

Body Membranes

cover surfaces, line cavities, and form protective lubricationg sheets around organs.

Types of Membranes

Epithelial- Cutaneous, Mucous, & Serous

Connective- Synovial

Cutaneous membrane

Is the skin- composed of stratified squamous epithelium.

Mucous Membrane

Lines all body cavities that are open to the exterior. EX: respiratory and digestive tracts.

Serous Membrane

Lines all body cavities that are closed to the exterior. Two layers parietal layer- covers walls of the cavity; visceral layer- covers the surface of the organs

Specific Serous membranes

Peritoneum- abdominal cavity and organs

Pluera- thoracic cavity and lungs

Pericardium- around the heart

Synovial membrane

Lines the fibrous capsules surrounding joints. Contains a synovial fluid that reduces the friction between the joints

Skin Functions

Protects deeper tissues from damage

Barrier (keeps things in and out)

Aids in heat loss and retention

Disposes of metabolic waste

Synthesizes vitamin D

Skin Structure

Epidermis- most superficial layer

Dermis- thick layer of connective tissue that contains glands, follicles, and vascular supply.

Hypodermis- layer of adipose (fat) tissue

Epidermis

composed of 5 layers (strata) from deep to superficial- basale, spinosum, granulosum, lucidum, & corneum

Melanin

Pigment that determines, skin, hair, and eye color. Derived from melanocytes in the basale layer of the epidermis

Freckle or mole

concentrated area of melanin

Papillary Layer

upper dermal layer that contains papillae which produce fingerprints, pain receptors, nerve endings, touch receptors (meissners corpuscles)

Reticular Layer

Deep dermal layer that contains; blood vessels, sweat and oil glands, pressure receptors (pacinian corpuscles)

Three pigments that produce skin color

Melanin, Carotene, and Hemoglobin

Skin appendages or derivatives

Sebaceous glands (oil), Sudoriferous glands (sweat), Hair, and Nails

Two types of sweat glands

Eccrine- most numerous found all over the body.

Apocrine- located in the axillary and genital regions empty into hair follicles, secrete a milky sweat.

Sebaceous gland functions

Secretes oil (sebum) onto the skin surface, lubricates & inhibits bacterial growth.

Hair

Produced by the hair follicle. Has a central medulla, surrounded by a cortex, and an outermost cuticle.

Arrector Pilli

small smooth muscle attached to follicle, when contracts it pulls the hair upright producing "goosebumps"

Burns

Tissue damage caused by heat, thermal, electrical, uv radiation, or chemicals

Rule of Nines

Universal method that divides the body into 11 regions each accounting for 9%

25% 2nd- Critical

10% ( or hands, feet, or face )3rd- Critical

First degree burns

only the epidermis is damaged (ie:Sunburn)

Second degree burns

the epidermis and upper dermis is damaged

blisters form

Third degree burns

The epidermis and whole dermis is damaged, the hypodermis is exposed. Grafting must be done in order to repair burn.

Dangers associated with burns

**Infection

Dehydration

Fluid & Electrolyte loss

Shock

Skin cancer

Rapid division of mutated epithelial cells.

Basal Cell Carcinoma

Least malignant, most common. Arise from the basale layer, removal of the lesion leads to 99% survival rate

Squamous Cell Carcinoma

Arises from the stratum spinosum. May metastasize to the lymph nodes if left intreated.

Malignant Melanoma

Most deadly. Arises from melanocytes. Can be detected by using the ABCD rule on moles.

ABCD Rule

Asymmetry- not the same on both sides

Borders- irregular (jagged) edges

Color- Not all one color a mixture of colors

Diameter- larger than 6 mm or larger than a dime