Ch 5: Integumentary System
What 2 pigments influence skin color?
*Melanin *Carotene
2 types of sweat glands
-->Apocrine sweat glands -->Merocrine sweat glands
_______ generally takes _____ days for cell to move from stratum ______ to stratum ________.
-->Cell Progression -->7-10 -->basale -->corneum
Two types of exocrine glands in the integument
-->Sebaceous glands -->Sweat glands
Five cell layers (strata) of thick skin from deep to superficial
->Stratum basale ->Stratum spinosum ->Stratum granulosum ->Stratum lucidum - only found in thick skin (palms, soles of feet) ->Stratum corneum
Two major parts of the integumentary system (or integument)
1. Cutaneous membrane, or skin 2.Accessory structures: -Hair -Exocrine glands -Nails
Keratin
Fibrous protein found in the epidermis, hair, and nails that makes those structures hard and water resistant; precursor in keratohyaline
Causes erythema or redness from inflammation
First-degree burn
Example: sunburn
First-degree burn
Nonliving, keratinized structures
Hair
-->Composed of flattened, densely packed cells filled with keratin -->Found only in thick skin
Stratum Lucidum
Clear Layer
Stratum Lucidum
Grainy layer
Stratum granulosum
Layer in which: _>Cells have stopped dividing ->Cells start making keratin
Stratum granulosum
Hair follicle
Structure with outer and inner root sheaths extending from the epidermal surface into the dermis and from which new hair develops.
Hypodermis
Subcutaneous tissue just deep to the skin; consists of adipose plus some areolar connective tissue.
Epidermis
Superficial layer of skin; composed of kerantinized stratified squamous epithelium.
Is 99 percent water with electrolytes, urea, and organic nutrients (Sodium chloride gives it the salty taste)
Sweat
Eccrine glands
Sweat glands abundant on the palms, soles of feet, and the forehead
Apocrine sweat gland
The less numerous type of sweat gland; produces a secretion containing water, salts, proteins, and fatty acids.
Pore
The surface opening of the duct of a sweat gland.
Damage may extend into the hypodermis
Third-degree burn
Epidermis and dermis are destroyed
Third-degree burn
Arrector pili
Tiny, smooth muscles attached to hair follicles; contraction causes the hair to stand upright.
Burn
Tissue damage inflicted by intense heat, electricity, radiation, or certain chemicals, all of which denature cell proteins and cause cell death in the affected areas.
Any cancer of epithelial tissue is a ...
carcinoma
Muscles become weaker and bone strength decreases due to...
decline in vitamin D3
produced by hair follicles
hair
portion that anchors hair into skin
hair root
hair part we see on the surface
hair shaft
Inhibits growth of bacteria, lubricates the hair, and conditions surrounding skin
sebum
Skin cancer found in more superficial layers
squamous cell carcinoma
Dead cells stay in the __________ __________ for two more weeks before being shed or washed away.
stratum corneum
Also called sudoriferous glands
sweat glands
First-degree burn
A burn in which only the epidermis is damaged.
Second-degree burn
A burn in which the epidermis and the upper region of the dermis are damaged.
Third-degree burn
A burn that involves the entire thickness of the skin; also called a full-thickness burn. Usually requires skin grafting.
Sebaceous glands (oil glands)
Epidermal glands that produce an oily secretion called sebum.
Produces "goose bumps"
Arrector pili muscle
Alopecia
Baldness.
The most common skin cancer? Originates in stratum basale
Basal cell carcinoma
Dead cells packed with keratin
Called keratinized or cornified cells
Malignant melanoma
Cancer of the melanocytes; can begin wherever there is pigment.
-->Orange-yellow pigment -->Accumulates in epidermal cells -->Found in orange-colored foods (carrots, squashes)
Carotene
-->Located in passageway of external ear -->Secretions combine with sebaceous gland secretions to form cerumen, or earwax
Ceruminous glands
Melanin
Dark pigment formed by cells called melanocytes; imparts color to skin and hair.
Contains -Blood vessels -Nerves -Hair follicles -Sweat glands
Dermis
Lies between the epidermis and hypodermis
Dermis
Sweat gland
Epidermal gland that produces sweat aka Sudoriferous Gland
Sudoriferous gland
Epidermal gland that produces sweat.
Dermis
Layer of skin deep to the epidermis; composed mostly of dense irregular connective tissue.
Malignant
Life threatening; pertains to neoplasms that spread and lead to death, such as cancer.
Superficial
Located close to or on the body surface.
-->Usually begins from a mole -->Can metastasize through the lymphatic system
Malignant melanoma
Most dangerous skin cancer?
Malignant melanoma
-->Structurally related to apocrine sweat glands -->Secrete milk
Mammary glands
-->Made by melanocytes -->Melanin absorbs UV radiation, protecting deeper layers of epidermis and dermis
Melanin
Function is to cool body through evaporation
Merocrine sweat glands
Rules of nines
Method of computing the extent of burns dividing the body into a number of areas, each accounting for 9% (or a multiple thereof) of he total body area.
Made of dense, keratinized cells and Protect dorsal surfaces of tips of fingers and toes
Nails
Sebum
Oily secretion of the sebaceous glands.
Cutaneous sensory receptors
Receptors located throughout the skin that respond to stimuli arising outside the body; part of the nervous system
Attached to hair follicles AND discharge oily lipid secretion (sebum) into hair follicles through holocrine secretion
Sebaceous glands
-->Causes blistering, pain, and swelling -->Some scar tissue may form
Second-degree burn
Entire epidermis and part of the dermis damaged
Second-degree burn
Integumentary system
Skin and its derivatives; provides the external protective covering of the body
Papilla
Small, nipple-like projection; e.g., dermal papillae are projections of dermal tissue into the epidermis
Contains: -->Stem cells that continually divide to replace cells lost at the surface -->Merkel cells (sensitive to touch) -->Melanocytes (synthesize melanin, a pigment)
Stratum Basale
Deepest layer of the epidermis Also called stratum germinativum
Stratum Basale
Contains 15-30 layers of flattened, dead cells packed with keratin
Stratum Corneum
Carotene
Yellow to orange pigment that accumulates in the stratum corneum epidermal layer and in fatty tissue of the hypodermis.
Secretion is sticky, cloudy, and potentially odorous
apocrine glands
Become active at puberty AND secrete into hair follicles in armpits, around nipples, and in pubic region
apocrine sweat glands
During cell progression in the epidermis, cells fill with ________ and die.
keratin
Also called eccrine sweat glands
merocrine sweat glands
Coiled tubular structure secretes watery perspiration directly onto surface of skin
merocrine sweat glands
