Anatomy & Physiology — Unit 3: "The Integumentary System."

Identify structures and function of nails:

Layers of keratinized cells. Produced at root, extends into finger or toe. No melanin, pink due to blood vessels. cuticle lunula nail body nail bed nail root

2nd Degree Burns:

Partial thickness. Through the epidermis and part of the dermis. Pain, redness. Blisters, may scar. 10-14 days, may take up to 105 days to heal.

Hemoglobin:

Pink color due to the blood vessels in the dermis.

Dermis (skin):

Connects epidermis via folded dermal papillae. Fibrous connective tissue, some loose areolar. Matrix is gel-like. Many collagen and elastic fibers. Thickness varies based on location. Contains muscle fibers (arrector pili) Contains blood vessels (capillaries) Contains nerve fibers and receptors. Hair follicles. Sebaceous glands, sweat glands, produces Vitamin D.

Hypodermis (not skin):

"Subcutaneous" Loose areolar and adipose (both connective) Fibers of collagen and elastin. Major blood vessels.

Explain various integumentary myths that may be selected for the exam:

(back page of note packet is time permits)

Label all parts of the skin diagram without terms:

- Epidermis. - Dermis. - Hypodermis. Nerve Endings. Veins. Arteries. Pore. Keratin. Stratum Germinativum. Connective Tissue. Sebaceous Glands. Arrector Pili Muscle. Hair Follicle. Hair Shaft. Sweat Glands. Adipose

Identify the functions of the integumentary System:

- To protect other organ systems from injury, foreign invaders, solar energy, fluid loss. - Regulates body temperature. - Synthesizes vitamin D. - Sensory reception.

Be able to outline steps for rebuilding tissue and scar formation after cut:

1. Clotting occurs, caused by clotting proteins and plasma proteins, a scab is formed. Inflammatory chemicals released, white blood cells deep into injured area. 2. Epithelial cells multiply and fill in over granulation tissue, which restores the vascular supply. 3. Retired epithelium thickens. The area matures and contracts. Underlying area of scar tissue, possible scaring.

Identify cause and characteristics of various abnormalities in pigmentation:

Albinism: lack of melanin, high risk for skin cancer. Recessive conduction caused by genetics (two heterozygous parents). Liver Spots: brown "age" spots, chase by accumulation of melanin. Carotene: build up caused by food consumption. Cyanosis: bluish color due to poor circulation, poor oxygen content in blood. Jaundice: liver not functioning properly. A yellow tint to the skin or eyes caused by an excess of bilirubin. Vitiligo: genetic (1/250) onset age 10 - 30. Symmetrical depigmentation of skin, no melanin production. Skin no longer uniform.

Diagram and define the stages of acne:

Blackhead: sebum and dead skin cells collect in ducts of oil glands and in hair follicle. Black color due to pigment melanin or exposure to air. Whitehead: when the plugged oil duct is sealed or covered with keratinized skin, bacteria may collect in a closed comedo. Pimple: rupture of a duct, sebum and bacterial infection is released into surrounding cells.

Melanin:

Blackish-brown pigment. Produced by melanocytes, located in the stratified germnativium, lowest layer of the stratified squamous tissue. Number of melanocytes is relatively the same, in darker skin, melanocytes produce more melanin at a greater rate.

Label the anatomy of a hair without terms (longitudinal and cross section):

Cross section: cortex medulla pigment granules cuticle scale Longitudinal: hair shaft pore hair root root sheath hair bulb matrix dermal papilla

Identify the specific changes in skin as a person ages:

Dermal layer becomes disorganized. Skin is more loosely attached. Adipose layer decreases, elderly may feel cold. Elastin and collagen become disorganized and decrease.

Freckles:

Flat concentration of pigment melanin. Genetically dominant, freckles are usually not present at birth, but increase with sun exposure.

Moles:

Flat or raised concentration of pigment. Can be present at birth, can be anywhere on the body, not just areas of sun exposure. Most moles are not a concern but pay attention to the ABCDEs of melanoma: Asymmetry, Borders, Color, Diameter, Evolving.

3rd Degree Burns:

Full thickness. Destroys the entire thickness of the skin. (all three) There is no pain as all nerves are destroyed. Also destroys vessels and glands. Risk for infection, loss of fluid.

Name the accessory structures of the integumentary system:

Hair: a source of heat insulation and cooling, protection from UV rays. Nails: support broad fingertips. Glands: secrete sweat and sebum.

Birthmarks:

Irregularity of pigment. May be small or large patch of discoloration. Two main categories of birthmarks: (1) Pigmented - brown, gray, blue or black. (2) Vascular (vessels) close to the surface. Red or purple in color. Port Wine Stain - type of common vascular birthmark.

Explain why solar energy is generally harmful but is necessary in small amounts:

Melanin provides for protection from Ultra Violet sunlight, dissipates 90% of absorbed UV radiation. Protects the DNA in the nuclei in cells from being destroyed or mutated, this prevents skin cancer. Limited sun exposure is helpful in that it promotes production of vitamin d, which is essential for bone health and maintenance. Lack of vitamin D can interfere with proper bone development and cause conditions like rickets, soft bones in children

Epidermis (skin):

Protects from mechanical injury, chemicals, microorganisms, etc. Absorbs light energy. Keratinization - top layer stratified corneum (stratified squamous) Cells flatten and push toward the surface for waterproofing, also prevents water loss. Stratum germnativium - lowest layer of the epidermis, newest cells. Pigmentation- location of melanocytes.

1st Degree Burns:

Superficial. Epidermis layer only. Redness and pain (ex. Sunburn) No scarring, less pain after 72 hours. Skin may peel.

Name the two major groups of glands and sub groups of sweat glands:

Sweat Glands: Apocrine - groin and armpits, release into hair follicle, active after puberty. Merocrine - surface of skin, lower body temp. mammary glands are modified sweat glands in females. Sebaceous Glands: produce oil (sebum), more active after puberty, associated with hair. May become clogged or infected.

Carotenes:

Yellow/orange color. Found in the foods that we consume. Not made by our skin, but can build up. Pigment which accumulates in our skin. Particularly in the adipose of the dermal layer.