Test 1b Flashcards
Cutaneous membrane and all appendages
Integumentary system
COnfines or hardens skin
Keratin
6 types of damages that the integumentary system protects against
mechanical, chemical, thermal, desiccation (drying out), ultraviolet, bacterial
What does the integumentary system do when skin is not open?
Acidic secretion on surface inhibits bacteria
What does the integumentary system do when skin is open
phagocytes ingest foreign substances and prevent contact iwht deeper tissues
4 functions of integumentary system
regulates body temperature, excretes salts, synthesizes vitamin D, senesory receptors convey information about external environment
2 tissue layers of the skin
Epidermis, dermis
What sort of epithelium the epidermis composed of?
Stratified squamous epithelium
What sort of tissue is the dermis composed of?
Dense connective tissue
Separation between dermis and epidermis that ocntains an accumulation of intersititial fluid
Blister
Not considered part of skin but anchors skin to udnerlying organs
Subcutaneous tissue/hyodermis
3 characteristics of hypodemris
Cushions, insultates, anatomical curves
How many layers of the epidermis
5
What produces keratin
Keratinocytes
Outermost layer of skin, dead
Stratum corneum
How does the stratum corneum protect deeper layers of skin?
Chemical and mechanical trauma, prevents water loss
How often is the stratum corneum replaced with new epidermis?
25-45 days
Not present in all skin regions, only where skin is hairless and thick
Stratum lucidum
Characteristic of stratum lucidum
Combination of accumulation of keratin secreting water-repllent glycolipid into ECM, increasing distance from blood supply
What happens as you move down the layers of the skin?
Layers become flatter and increasingly more keratinized
Lies closest to dermis
Stratum basale
How is nourishment delivered to stratum basale?
Diffusion from dermis through epidermal cells
What 2 substances is the dermis mainly composed of?
collagen, elastin
Upper layer of dermis
Papillary layer
The uneven, peg-like projections that indent the epidermis
Dermal papillae
Deepest layer of skin
Reticular layer
Another name for stretch marks
Linea albicans
3 pigments that contribute to skin color
melanin, carotene, hemoglobin
Where is melanin found?
epidermis
where is carotene found
stratum corneum, subcutaneous tissue
Where is hemoglobin found
dermal blood vessels
What is melanin produced by
melanocytes
What does sunlight do to melanocytes
stimulates them to produce more melanin
What layer of the epidermis is melanin primarily found in
stratum basale
How is the number and distriubiton of melanocytes determined?
genetics
Redness from fever, inflammation, allergy, etc.
Erythema
Paleness from anemia, fear, stress, low blood pressure
pallor
yellowness from liver problem
jaundice
blueness from poor oxygen content in blood
cyanosis
black and blue from blood escaped from vessels and has clotted in tissue spaces due to trauma
bruising
2 types of exocrine glands
sebaceous, sweat
Where are exocrine glands formed
stratum basale
Where are sebaceous glands found?
All over, except palms and soles of feet
Main function of sebaceous glands
Producing sebum
4 characteristics of sebum
greasy, lubricates skin, contain chemicals that kill bacteria, prevent hair form becoming brittle
2 types of cutaneous sweat glands
apocrine, eccrine
4 substances that sweat is made of
water, salts, metabolic waste, lactic acid
How does sweat reach the skin?
Duct/funnel-shaped pore
Where are apocrine glands concentrated within the body?
Axillary and genital areas
Where is the matrix (growth zone) of hair
Stratum basale epithelial cells
Part of hair that is enclosed in hair follicle
root
Part of hair that projects to the surface
Shaft
Part of hair that is the central core
medulla
Part of hair that surrounds medulla
cortex
Part of hair that surrounds cortex with its single layer of scale-like cells
cuticle
4 characteristics of cuticle
heavily keratinized, keeps hairs separated, wears away at end, mealnocytes i hair bulb produce pigment to determine color
Causes slanting of hair that contract when we are afraid or cold
Arrector pili muscles
5 ways homeostasis is lost in skin
burn, cancer, open wounds, allergies, infections
Tissue damage and cell death caused by intense heat in the form of chemical, thermal, UV radiation or electrical agents
burns
How many parts does the rules of nines divide the body into?
11 areas (9%) and genitals (1%)
How are burns classified?
Severity/depth
What percent is second degree burn?
25%
What percent is third degree burn?
10%
Associated with inhalation burns and can cause respiratory damage and swelling
Facial burns
Only epidermis damaged, red and swollen, temporary discomfort
First degree burn
What degree burn is a sun burn?
First degree burn
Injury to epidermis and upper level of dermis; red, swollen, blisters, and painful
Second degree burn
In a second degree burn, is regeneration of skill possible?
Yes
Destroys entire thickness of skin; gray-white, black
Third degree burn
Are third degree burns painful?
No
In a third degree burn is regeneration possible?
No
Greatest risk factor for skin cancer
Over-exposure to sunlight
Most common skin cancer
Basal cell sarcoma
What cells does basal cell sarcoma effect?
Cells of stratum basale
Skin cancer that arises from stratum spinosum
Squamous cell carcinoma
Where does squamous cell carcinoma usually metastasize to?
Lymph nodes
Cancer of melanocytes that arises from pigmented mole
Malignant melanoma
Where does malignant melanoma usually metastasize to?
Lymph nodes or blood vessels
5 ways to examine pigmented areas
Asymmetry, Border irregularity, Color, Diameter, Elevation
Forms from prolonged external pressure over bony prominences
Ischemic necrosis
Acute or chronic skin inflammation; itching, redness, and swelling
Contact dermatitis
3 everyday examples of contact dermatitis
Poison ivy, latex, soaps
Auto-immune disorder that attacks tissues that is triggered by stress, trauma, hormones, infections
Psoriasis
What does psoriasis result in?
Overproduction of cells; dry, scaly, cracking red lesions
Transmissible paraisitic infection where mite burrows into stratum corneum and burrow egs
Scabies
Fungal infection between toes
Athlete’s foot
Birthmark of hyperplasia vascular lesion of skin and subcutaneous tissue
Port wine stain
Excessive proliferation of connective tissue during healing of open skin
Keloid scarring
Inherited, autosomal recessive disorder that is missing enzyme that makes melanocytes to produce melanin
Albinism
Hypersensitivity reaction similar to allergy that leads to inflammation of skin
Eczema
Loss of brown pigment form areas of skin with irregular white patches; melanocytes die or are unable to function
Vitiligo
