Body's most accessible organ and first line of defense against environment
Integumentary System
Skin condition that occurs when hair follicles & oil sweat glands become clogged - leading to pimples. white heads, black heads, and other skin lesions
Acne
Which dermal layer is under the dark purple epidermal ridges of loose CT?
Hint: layer under epidermis
Papillary Layer
What is the first layer of the epidermis?
Hint: Can Lemurs Grab Some Basal?
Stratum Corneum - outermost protective layer; sheds every 2 weeks
True or False: Fibers in the dermis become less elastic and organized as we get older.
True
What are the 3 main functions of the Integumentary system?
1. protect underlying tissues & organs
2. Excretion of salts, water, & organic wastes
3. maintenance of homeostasis
Autoimmune chronic skin condition that causes raised, inflammed, red plaques that are often covered with silvery-white scales
Psoriasis
Which dermal layer is at the bottom with dense CT?
Hint: layer under epidermis & dermis
Reticular Layer
What is the 2nd layer of the epidermis?
Hint: Can Lemurs Grab Some Basal?
Stratum Lucidum - clear layer, flattened keratinized cells, absent in thin skin
True or False: Aging skin has more elastic and collagen fibers than younger skin.
False; younger skin produces more and cells are stronger
What pigment and protein does the integument produce?
melanin = pigment
keratin = protein
A painful skin rash caused by varicella zoster virus (VZV), the same virus in chickenpox. - Not contagious, but can get chickenpox from someone with this.
Shingles
What is the epidermis?
outermost layer of the skin; 5 layers of stratified squamous epithelium
What is the 3rd layer of the epidermis?
Hint: Can Lemurs Grab Some Basal?
Stratum granulosum "grainy layer" - 3-5 layers of keratinocytes; living cells stopped dividing, makes keratin
What are 3 behavioral habits you can do to reduce advanced aging of your skin?
stress reduction, eating healthy, sleep, exercise, reduce sun exposure, avoid smoke and pollutants
What are the 3 cutaneous membrane layers of the skin?
Epidermis, Dermis, Hypodermis
sacs of tissue that can form anywhere in the body, but most commonly on skin, ovaries & kidneys.
-typically full of pus, but can have fluid, keratin, hair, tissue & even bone filled sacs of tissue
Cysts
What is the dermis?
thick layer of living tissue below the epidermis that forms the true skin
contains papillary & reticular layer with blood & lymphatic vessels, fibers, & sensory neurons
What is the 4th layer of the epidermis?
Hint: Can Lemurs Grab Some Basal?
Stratum Spinosum "spiny layer" - 8-10 layers, defend againt pathogens & superficial cancers
Why doesn't newly healed skin always regain full abilities?
Hint: think about how a wound heals itself
healing process prioritizes closing the wound (blood clots & scabs) over restoring all original functions
What are the accessory organs of the skin?
Hair, sebaceous glands & sweat glands
Highly contagious, common parasitic infection where mites burrow into the skin and eat the host, which is the epidermis
Scabies
What is the hypodermis?
NOT part of integument, but separates deeper tissues & stabilizes position of skin
mostly adipocytes for energy storage
What is the 5th layer of the epidermis?
Hint: Can Lemurs Grab Some Basal?
Stratum Basale "basal layer" - basal (stem) cells attached to the basal lamina actively dividing to replace cells lost on superficial layers
Why do tattoos remain visible in the skin for long periods of time, despite the body's natural process of shedding skin cells?
tattoo pigments are embedded deep in the dermis where cells are more stable and don't shed like the epidermis