2.2 Integumentary System Flashcards
Which other body systems are most closely integrated with the integumentary system?
Cardiovascular- lots of vessels
Nervous- lots of nerves
What makes up the integumentary system?
Cutaneous membrane (Skin) Epidermis Dermis Subcutaneous layer Accessory structures Hair Nails Glands
What are the many functions of the integumentary system?
Protection – pathogens, UV radiation, harmful chemicals
Waste Excretion – excess salts, water, organic waste
Body Temperature – insulation, cooling
Production of melanin – pigment against UV radiation
Production of keratin – tough, water repellant surface
Synthesis of Vitamin D3 – involved in calcium metabolism
Fat Storage – adipose tissue
Sensation – touch, pressure, pain, vibration, temperature
Immune Response – 1st layer of defense, inflammation
What are the layers of the epidermis?
"Come, let's get sun burned" superficial--> deep · From superficial to deep: Corneum Lucidum Granulosum Spinosum Basale
Describe the process of keratinazation
Keratinized stratified squamous only found in skin
Keratin a protei
Surface layers dead, lose most organelles, replaced with keratin
Film of glycoproteins that protect skin by waterproofing
Epithelium, therefore avascular, received everything from dermis below
*No bleeding from an injury contained to the epidermis (bc no vasculature)
Continually replaced by proliferative stem cells in stratum basale
What is they function of keratinocytes?
Majority (99.9%) of skin cells
Produce a protein called keratin
keratin: water resistant, tough, fibrous protein related to intermediate filament protein
Cells on surface have more keratin, cells on surface die from so much keratin
Keratinocytes is the stratified squamous epithelial cells
What is the function of melanocytes?
Produce a pigment called melanin
Cytoplasmic processes inject vesicles of melanin into keratinocytes
Melanin absorbs UV radiation, helps prevent tissue and DNA damage
Large cells, produce pigments, seen deeper in epidermis, towards stratum basale
Skin tone/hair color comes from levels of melanin in the tissue. Everyone has the same number of melanocytes, but the extent to how active they are is genetically derived
How are skin and hair colored? How does this capability vary between people?
All people have the same relative numbers and types of skin cells, but the levels of pigment production vary across individuals Skin and hair color are due to: melanin: yellow-black genetically determined pigment pheomelanin: red-yellow eumelanin: brown-black other influences on skin color bilirubin levels: yellow, jaundiced carotene (dietary): orange-yellow blood flow: increased circulation pink/red decreased blood flow pale, white lack of oxygen cyanotic (blue)
What is albinism?
genetic reduction in melanin pigment in skin, hair and/or eyes
sensitivity to light, optic conditions
range in severity and affected structures
sensitive to UV damage
difficulty with vision common with albinism, lack of melanin creates sensitivity
What is vitiligo?
Discolored patches of skin due to loss of melanocytes
acquired condition increased in autoimmune and thyroid dysfunction
A “patch” of melanocytes are killed, causing vitiligo.
What is melasma?
hyperpigmented areas of skin on face
common with pregnancy (aka chloasma), sun damage
What are lentigos?
large pigmented spots on hands, forearm, face
age and sun-exposure related, aka “age-spots”
What is the difference between thick and thin skin?
Thick skin: found on palms of hands, soles of feet
all 5 layers (strata), thicker stratum corneum
n palmar/plantar surface. Extremely thick stratum corneum. Thick skin doesn’t have hair.
Thin skin: found on rest of the body
4 layers (strata), no stratum lucidum, thinner stratum corneum
On the majority of the body. Only 4 layers. No stratum lucidum
What causes fingerprints?
Dermal ridges pressing upon the epidermis
What are the two layers of the dermis? What type of tissue is the dermis?
Papillary layer
Reticular layer
Mostly connective tissue
Describe the papillary layer
layer just underneath the epidermis
areolar connective tissue
Dermal papillae -form epidermal ridges
blood vessels, lymphatic vessels, nerves, sensory cells
forms bumps that push up unto epidermis, deep to epidermis, primarily areolar CT
BC areolar CT, has vasculature, nerves
Describe the reticular layer
deepest layer, dense irregular connective tissue
blood vessels, lymphatic vessels, nerves, sensory cells, base of hair follicles, glands
Describe the subcutaneous layer
(hypodermis or superficial fascia)
Deep to the dermis, mostly adipose and some areolar CT
Anchors skin to underlying muscle
Allows skin to slide relatively freely
Energy reserve, insulation, shock absorber
What is an abscess?
buildup of pus (inflammation, white blood cells, bacteria) in or on the skin, multiple causes
bacterial infection (often staphylococcus)
wound or injury
boils
folliculitis
warm compress, drainage, may need to be further cut open, cleaned and drained
if untreated, can spread to nearby areas, spread to the blood, other organs, lead to localized tissue death (gangrene).
What is a nevi?
“moles”, pigmented or depigmented benign skin tumors
What is the acronym for skin lesions/cancer?
ABCDE: asymmetry Border- irregular Color- varied Diameter- >6mm Evolving
What is actinic keratosis?
patches of rough, scaly, red plaques
common with fair skin and sun-damage
What are the three types of skin cancer?
Melanoma Basal cell carcinoma Squamous cell carcinoma -oma= tumor carcinoma= cancer of epithelial tissue
What is melanoma? What are some risk factors?
cancer of melanocytes, spreads to up epidermis, then through dermis where it can metastasize
brown, black, or light colored bump or growth
risk factors: fair skin, multiple moles, irregular moles, history of tanning or sunburn, family history, immunosuppression, age over 50.
most concerning when penetrates down to dermis- b/c mets can come from access to lymph/blood systems