aapc fundamentals of medicine ch.2

The largest organ in the human body is the

skin/ integumentary system

The integumentary system consists of

skin, hair, nails, and several exocrine glands

Skin is another word for

integument

Exocrine glands are

Glands whose secretory products are transported via ducts

What does skin do

guards from injury, protects against infection, and controls temperature.

Exocrine glands include

lacrimal glands, which produce tears. sweat glands that produce sweat. salivary glands, which produce saliva. digestive glands, producing digestive fluid. and mammary glands that produce milk.

Digestive glands are found in

the stomach, pancreas, and intestine

Cutaneous (cutis- lantin for skin)

pertaining to the skin

cutaneous sensation

a feeling of touch, pressure, vibration, tickle, heat, cold, or pain that arises in the skin

derma (Greek for skin)

derma is a combining word, which means it can combine to the beginning of a word or the end. (ex: dermatologist, scleroderma)

-itis

inflammation

-malacia

softening

-oma

tumor

-osis

condition of

-pathy

disease

-rrhea

excessive discharge

derm/o

skin

dermat/o

skin

hidr/o

sweat, perspiration

hyp/o

under, below, deficient

kerat/o

keratin, horny tissue; hard; cornea

mamm/o

breast

melan/o

melanin, black, dark

myc/o

fungus

onych/o

fingernail or toenail

scler/o

hard, thick

seb/o

sebum

trich/o

hair

xer/o

dry

The skin is made up of two layers

epidermis and dermis

Epidermis

Outer layer of skin

Dermis

Inner layer of skin

How many layers make up the epidermis

five

stratum corneum

surface layer of the epidermis, periodically cast off or shed

stratum basale

The foundation of the epidermis, the deepest layer

stratum lucidum

Clear, transparent layer of the epidermis under the stratum corneum. covers the palms of the hands and the surface of the feet.

stratum granulosum

3rd layer of the epidermis, granular layer

stratum spinosum

spiny layer, composed of prickle cells that are interwoven for protection

Melanocytes

produces melanin, base of the epidermis, gives the skin its pigment

Dermis, or the middle layer, contains

blood vessels, lymph vessels, hair follicles, sweat glands, collagen bundles, fibroblasts, nerves, and sebaceous glands.

blood vessels

tubelike structures that carry blood throughout the body

lymph vessels

small tubes that carry lymph fluid throughout the body

Hair follicles

Tube-like pockets of epidermal cells that extend into the dermis, responsible for growing hair

sweat glands

The glands that secrete sweat, located in the dermal layer of the skin. also known as the sudoriferous or sudoriparous glands

collagen bundles

Strong fibers that support most tissues and provide cell structure.

Fibroblasts

In connective tissue, cells that secrete the proteins of the fibers.

nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

sebaceous glands

oil glands in the skin

dermis is bound together by a protein called

collagen

collagen

gives skin mobility and stability

The dermis has two stratum layers called what?

stratum papillare and stratum reticulare

Stratum papillare

Thin external layer woven with the epidermis

Stratum reticulare

thick layer of dense, irregular connective tissue

Subcutaneous fat layer (hypodermis)

composed of a weave of collagen and fat cells, supports preserving body temperature and protects from injury by acting like a cushion; its main function is to anchor the skin to the underlying muscles

superficial fascia

loose/ fibrous connective tissue that underlies the skin and attaches it to the superficial layer of muscles

Skin tags (acrochordons)

simple benign growths of skin that aren't cancerous, attached to the skin surface by a stalk, more common in elderly, obese, and diabetic pt's

three major types of skin cancer

basal cell carcinoma, squamous cell carcinoma, melanoma

basal cell carcinoma (BCC)

malignant tumor of the basal layer of the epidermis; the most common type of skin cancer

squamous cell carcinoma (SCC)

skin cancer that begins in the epidermis but may grow into deeper tissue; it does not generally metastasize to other areas of the body

Melanoma

The most serious form of skin cancer

Kaposi sarcoma (KS)

Cancer caused by the human herpes virus 8 (HHV-8) that mainly affects the skin and mucous membranes but may also cause extensive visceral organ involvement; also called malignant neoplasm of soft tissue

Folliculitis

infections of the hair follicles

arrector pili muscles

Muscles causing hair to stand up.

Medulla

core of hair

cortex

bulk of the hair follicle

hair shaft

visible part of the hair

keratin

hard protein material found in the epidermis, hair, and nails

root

lies beneath the cuticle in a groove

portion of the nail you can see

nail body

Lunula

The half-moon-shaped, whitish area at the base of a nail

nail bed

Portion of the living skin that supports the nail plate as it grows toward the free edge.

Cyanosis

bluish discoloration of the skin

lamellar corpuscle

detects pressure deep in the dermis

sensory receptors

sensory nerve endings that respond to stimuli

glands located in the skin

sebaceous glands and sweat glands

three types of sweat glands

eccrine, apocrine, and apoeccrine

eccrine sweat glands

found in palms, soles of the feet, and forehead, primarily secrete water and electrolytes

apocrine glands

Sweat glands in the pubic and underarm areas that secrete thicker sweat, that produce odor when come in contact with bacteria on the skin

apoeccrine gland

simple tubular, found primarily in the axillae, larger than eccrine glands but smaller than apocrine glands, most open into hair follicles but continuously secrete a thin, watery sweat

The breast consists of two regions

circular body (largest part) and axillary tail (smallest part)

most common inflammatory disorders of the skin

eczema and dermatitis

eczema

Noncontagious skin rash that produces itching, blistering, and scaling (makes skin red and inflamed)

Psoriasis

chronic, recurrent dermatosis marked by itchy, scaly, red plaques covered by silvery gray scales (skin is thicker and more inflamed)

Allergic contact dermatitis

Abbreviated ACD; an allergy to an ingredient or a chemical, usually caused by repeated skin contact with the chemical.

Irritant contact dermatitis

ICD; occurs when irritating substances temporarily damage the epidermis

atopic dermatitis

Excess inflammation; dry skin, redness, and itching from allergies and irritants. (tends to be associated with asthma and hay fever)

stasis dermatitis

chronic inflammatory state in the legs due to poor circulation; the legs may sometimes have ulcerations, along with scaly skin, itching, and hyperpigmentation

seborrheic dermatitis

an inflammation that causes scaling and itching of the upper layers of the skin or scalp

papules

small well well-defined bumps in the skin

Furuncles

boils; large, tender, swollen areas caused by a staphylococcal infection around hair follicles or sebaceous glands

scales

flakes or dry patches made up of excess dead epidermal cells

plaque

a solid mass greater than 1 cm in diameter and limited to the surface of the skin

Erythema

redness of the skin

pityriasis rosea

small itchy rash, red in color. mostly seen in young adults

Lichen Planus

Benign, chronic disease that affects the skin and oral mucosa

acne vulgaris

severe acne

acne rosacea

chronic form of acne seen in adults involving redness, tiny pimples, and broken blood vessels, primarily on the nose and cheeks

Infections of the skin are known as

cutaneous infections

types of infection

bacterial, viral, fungal

bacterial infections

Develop when microbes invade an injured, open or wounded part of the body