SKINS AND MEMBRANES

Cutaneous membrane

Mucous membrane

Serous membrane

3 types Epithelial membranes

Cutaneous membrane = skin

A dry membrane

Outermost protective boundary

MUCOUS MEMBRANE

Lines all body cavities that open to the exterior body surface

SEROUS MEMBRANE

• Surface simple squamous epithelium

• Underlying areolar connective tissue

Peritoneum (Abdominal cavity)

Pleura (Around the lungs)

Pericardium (Around the heart)

Specific serous membranes (ABDOMINAL CAVITY, LUNGS, HEART)

Connective tissue

Synovial membrane

INTEGUMENTARY SYSTEM

• Skin (cutaneous membrane)

• Skin derivatives

- Sweat glands

- Oil glands

- Hairs

- Nails

Mechanical damage

Chemical damage

Bacterial damage

Thermal damage

Ultraviolet radiation

Desiccation

SKIN FUNCTIONS, Protects deeper tissues from:

Epidermis – outer layer

Stratified squamous epithelium, outer layer of?

Stratum basale (Cells undergoing mitosis Lies next to dermis)

Stratum spinosum

Stratum granulosum

Stratum lucidum (Occurs only in thick skin)

Stratum corneum (Shingle-like dead cells)

Layer of Epidermis

STRATUM BASALE

Cells undergoing mitosis, Lies next to dermis

MELANIN

Pigment produced by melanocytes

Color is yellow to brown to black Melanocytes are mostly in the stratum basale

Amount of melanin produced depends upon genetic and exposure to sunlight

MELANIN

Yellow, brown or black pigments

Carotene

Orange-yellow pigment from some vegetables

Hemoglobin

Red coloring from blood cells in dermis capillaries

Oxygen content determines the extent of red coloring

CYANOSIS

Low oxygen content creates a bluish appearance

DERMIS

Dense connective tissue, Has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures.

PAPILLARY LAYER

RETICULAR LAYER

2 LAYERS OF DERMIS

PAPILLARY LAYER

Projections called dermal papillae

Pain receptors

Capillary loops

RETICULAR LAYER

Blood vessels

Glands

Nerve receptors

HYPODERMIS

Deep to dermis

Not part of the skin

Anchors skin to underlying organs

Composed mostly of adipose tissue

Sebaceous glands

Sweat glands

2 types of glands

Sebaceous glands

Produce oil

Lubricant for skin

Kills bacteria

Most with ducts that empty into hair follicles

Glands are activated at puberty

Sweat glands

Widely distributed in skin

Two types (Eccrine, Apocrine)

(Eccrine, Apocrine)

Two types of sweat glands

ECCRINE SWEAT GLANDS

Open via duct to pore on skin surface

Apocrine sweat gland

Ducts empty into hair follicles

HAIR

Consists of hard keratinized epithelial cells

Melanocytes provide pigment for ____ color

Central medulla → Cortex → Cuticle

Hair Anatomy

NAILS

Scale-like modifications of the epidermis

Heavily keratinized

First-degree burns

Only epidermis is damaged

Skin is red and swollen

Second degree burns

Epidermis and upper dermis are damaged

Skin is red with blisters

Third-degree burns

Destroys entire skin layer Burn is gray-white or black

CANCER

abnormal cell mass

Benign Does not spread (encapsulated)

Malignant Metastasized (moves) to other parts of the body

Two types of skin cancer

A = Asymmetry Two sides of pigmented mole do not match

B = Border irregularity Borders of mole are not smooth

C = Color Different colors in pigmented area

D = Diameter Spot is larger then 6 mm in diameter

ABCD Rule

Melanocytes

Melanin, Pigment produced by?