Integumentary System (Your Skin) Flashcards
What does the integumentary system include?
Skin Hair Oil and sweat glands Nails Sense receptors (touch, hot/cold)
Subcutaneous layer
Lies under skin layers
Areolar and adipose tissue
Storage depot
Skin layers
Epidermis (top layer)
Superficial layer
Epithelial tissue
Dermis (underneath)
Mainly connective tissue with elastic fibers
3 pigments make up skin color
What 4 cell types does the epidermis contain?
Keratinocytes
Melanocytes
Langerhan cells
Merkel cells
Epidermal layers? Thick vs thin
Mostly thin skin - 4 layers on body
Thick skin - 5 layers (palms and soles of feet)
What are the 5 layers from deepest to superficial?
Stratum basale (how cells are made, bottom) Spinosum Granulosum Lucidium (only in thick) Corneum (top layer)
What happens during keratinization ?
New cells made in the stratum basale layer
Cells move up from one epidermal layer to the next.
Definition- Accumulate more keratin as they move to top of skin
Dead cells slough (fall) off
Takes about 4 wks from stratum basale to rise to surface
- excessive amount shed from scalp is DANDRUFF
What’s dandruff
Excessive amount of dead keratin cells shed from the scalp (part of keratinization process)
What does the dermis layer include?
- type of tissue?
- what does it have?
Dense irregular connective tissue -collagen and elastic fibers Divided into 2 regions -papillary: more superficial -reticular: deeper
What is in the papillary region ? (In the dermis)
(Superficial) -areolar tissue with elastic fibers DERMAL PAPILLAE: finger-like projections that project into epidermis - finger print region - contain blood capillaries -nerve endings (sensory receptors)
What are the nerve endings in the dermal papillae in the papillary region in the dermis region? (2)
Meissner corpuscles- touch
Free nerve endings- warmth, pain, coolness, tickling, itching
What does the reticular region include in the dermis region?
- tissue?
- has?
(Deeper) -attached to subcutaneous layer -dense irregular connective tissue w/ collagen and elastic fibers Provides: -skin strength -extensibility -elasticity Hair follicles, nerves, oil glands, sweat glands
What 3 pigments produce skin color?
Melanin
Hemoglobin
Carotene
What in the cell causes cancer?
When the nucleus mutates (why when melanocytes are produced, then protect the nucleus)
Melanin distribution can result in albinism
What is albinism
Inherited trait where no melanin is produced
Melanin distribution can result in freckles
What are freckles?
Melanin accumulates in patches
Melanin distribution can result in age spots
What are age spots?
Melanin accumulation with age & forms flat blemishes
Melanin distribution can result in Nevus (mole)
What is nevus
Localized overgrowth of melanocytes
-round, flat, or raised areas
Melanin distribution can result in vitiligo
What is vitiligo?
Condition where melanocytes are partially or completely lost from areas of skin
-irregular white areas on skin
What is hemoglobin?
O2 carrying pigment molecules in red blood cells (why we blush!)
In light skin, plays larger role in reddish hue of skin
-oxygen content in epidermal capillaries
What’s carotene?
Yellow-orange pigment
Precursor of Vitamin A
Accumulates in stratum corneum (top layer of skin) and fatty dermis areas
What is melanin?
Amount and shades produce all skin colors
-pale yellow to black
Absorbs UV light for protection
Melanocytes (produce melanin) in stratum basale and mucous membranes in body
All races have equal # of melanocytes
Difference in color is amount of melanin produced (ancestors location determine melanin production, evolutionary history!)
Skin/ integumentary system is also known as?
Cutaneous membrane
Hair
- what is it?
- location?
- description?
- types?
Columns of dead, keratinized epidermal cells
Not on soles of feet or palms
Hair thickness and pattern determined by genetics and hormones (it’s hereditary, gray early)
Body hair, scalp hair, eyebrows/eyelashes
Body hair
Sense light touch
Scalp hair
Protects from UV light and decreases heat loss
-lose about 70-100 scalp hairs per day
Eyebrows/eyelashes
Protect eyes from particles
What glands do we have?
Sebaceous (oil) glands
Sweat glands
Ceruminous glands
Sebaceous glands
What are they?
Location?
Function?
Oils glands Connected to hair follicles Secrete sebum -lipids and cell debris (dead skin & hair cells) Function: -softens skin, waterproofing surface - blackheads - pimples and boils
Blackheads
Enlarged sebaceous glands with accumulated sebum
Pimples and boils
Bacteria metabolizing sebum
Sweat glands
What are they?
Location? Function?
Sudoriferous glands 3-4 million per person Deep dermis, subcutaneous layers Release sweat into hair follicles or on skin surface through pores Two main types: Eccrine & Apocrine sweat glands
Eccrine sweat gland characteristics
Most common sweat gland
Located throughout body regions
Produce watery sweat that regulates body temp.
Apocrine sweat gland characteristics
Limited to axillary (armpit) and public regions
Produces thicker sweat; often released during emotional stress
Water w/ electrolytes & metabolic waste
(Release into hair follicles!)
Ceruminous glands
Earwax glands In ear canal & outer ear Secrete cerumen -lipids and cell debris -prohibits entry of debris from entering eat canal
Nails
What are they?
Function?
Plates of hard, tightly packed dead keratinized epithelial cells of epidermis
Function: -protect ends of fingers & toes
- Aids in grasping objects
Accessory structure of the integumentary system include?
Hair nails and glands
Pathology of the skin includes
Acne, burns, and skin cancer
Acne
How is it caused?
What is it actually called?
Acne vulgaris- affects 96% of adolescents & young adults to some degree
Cause- accumulation of sebum and dead cells within sebaceous glands
-occasionally infected with bacteria resulting in inflammation & formation of a pustule (pimple)
Male sex hormones (like TESTOSTERONE) are primary cause
Wounds
What do they include?
Definition?
Common skin pathology; defined as any disruption in skin's integrity Includes: -lacerations (cuts) -burns -skin cancers
Cancer
Definition?
Cause?
One of the most common diseases in the world; caused by mutations in DNA that induce a cell to lose control of cell cycle
(Cancer), unchecked cell division
Leads to?
This eventually leads to formation of a large population of undifferentiated cells known as a tumor
What are cancerous tumors about to do?
They are able to metastasize
-tumors cells spread through blood or lymphatic vessels to other tissues & continue to divide
Most, but not all cancer cells do this. SPREAD, circulated throughout the body!
How many cancers affect the skin?
What are they linked to?
3
Linked to UV radiation exposure
What are the other factors that can increase risk for developing cancer, besides UV exposure
Exposure to:
- Cancer-inducing chemicals, toxins or agents called carcinogens
- Forms of radiation
Norciceptors
free nerve endings that sense pain rapidly. other free nerve endings sense tickle, itch, and some touch
Merkel (tactic) disc
slowly sense touch near surface (skin receptor)
Meissner corpuscle
rapidly senses touch near surface (skin receptor)