Integumentary System, Samantha Robles p.5

Function of the Integumentary System

Skin Cancers

Body Membranes

Layers of Dermis

Layers of the Skin

Layers of Epidermis

Acessory Organs

Mucus Membrane (mucosa)

Synovial Membrane

Serous Membrane (serosa)

Cutaneous Membrane (skin)

Dermis (inner layer)

Hypodermis (uderlying layer)

Epidermis (outer layer)

The Integumentary System covers skin, hair, glands, nails. Integument's function would be the regulation of the body temperature, touch, vibration and pain. It's extraction wastes in form of urea (sweat).

Primary Organ of the Integumentary System, takes up 15-16% of body weight. Has two layers the first one is the Superficial Epithelial layer (Keratinized stratified squamous epitilium). The second layerr is the Deep supportive connective tissue.

Lines the body cavities and covers organ surfaces. Contains two types of tissues. The first one i Simple squamous epithelial layer. The second one is the Loose Connective tissue.

Contains epithelial cells, Goblet cells that present mucus production. Mucus restricted to respriatory tract. That is called phlegm in nasal passages.

Connective tissue, soft areolar, NO EPITHELIAL TISSUE. Located in the fibrous line capsules surrounding joints. Its functions roduces synovial fluid, lubrication, reduce friction line bursae (sacs, around joints). Cusions organs moving against each other.

Benign: does not spread and grows slowly

  1. Stratum spinosum
  1. Reticular Layer

Nails

Apidose tissue. Anchors skin to the underlying structures. Shock absorber and unsulator to reduce heat loss.

Dense fiborus CT with collagen and elastic fibers. Much THICKER. Contains blood vessels, nerve fibers etc.

Keratinized stratified squamous epithelium. Avascular (WITHOUT BLOOD CELLS). Oxygen and nutrients disffuse from dermis.

3.Stratum granulosum

  1. Stratum lucidum
  1. Stratum basle

5.Stratum corneum

Deepest layer closest to the dermis, basement membrane constantly dividing (mitosis), 90% keratinocytes, 10% melanocytes.

Several cell layers thick of flattened cells, 8-10 cells thick, mitosis, DESMOSOMES.

very thin region 3-5 layers, last layer the obtains nutrients from difusion, begins kertinization, cells die here, cells "toughen up" here.

2-3 layers clear, flat, dead, cells, translucent layer

outer most layer 20-30 cells thick up to 200, protection against abrasion and penetration, water repellant.

  1. Papillary Layer

Thin superficial layer, areolar connective tissue, loose connective tissue, superior surface is called Dermal Papillae, directly under the epidermis, contains light touch receptors called Meissner's corpuscles.

Deepest layer, dense connective tissue, 80% of the thickness of the dermis, lots of blood vessles matrix contains thick bundles of collagen fibers and elastic fibers.

sweat glands

sebaceous (oil) glands

hair

Malignant: grows relentlessly