Integumentary Test 1 Flashcards
What is the integumentary system made up of?
(AKA Cutaneous Membrane)
Skin Hair, Oil/Sweat glands Nails Sensory receptors
2 main parts of skin
Epidermis: is avascular
Dermis: is vascular (has blood vessels)
Skin size
Largest organ of the body. on average covers a surface of 2 meters squared
Functions of skin
Protects body from external environment • Thermoregulation • Excretes and absorbs substances • Stores blood (around 8-10%) • Detects cutaneous sensations • Synthesizes vitamin D (10-15 minutes of sun to begin)
Skin layers
Epidermis *superficial layer
Dermis: Deep layer
Epidermis cells Types
Keratinocytes
Melanocytes
Macrophages
Tactile epithelial cells
Types of skin
Thin and Thick
Components of thick skin
Stratum basale Stratum spinosum Stratum granulosum Stratum lucidum Stratum corneum
Components of thin skin
Stratum basale:
Stratum spinosum
Stratum granulosum
Stratum corneum:
Present in thick skin but not thin
Stratum lucidum
Dermis characteristics
Second, deeper part of the skin
o Composed of mainly collagen fibers and some elastic fibers
o Contains blood vessels, nerves, glands, hair follicles
o Divided in 2 regions (pappillary and reticular)
Papillary Region
-part of dermis
Make up 1/5 the thickness
• Contain tactile corpuscles (Meissner corpuscles
Reticular region characteristics
Makes up 4/5 of the thickness of the dermis
• Combination of collagen and elastic fibers here gives skin the ability to
stretch (extensibility) and recoil (elasticity)
• Contains blood vessels, nerves, hair follicles, sebaceous glands and
sudoriferous glands
Epidermal ridges
- can be found on the surfaces of the palms, palmar surfaces of the digits, soles, and plantar surfaces of the toes
- produced during the third month of fetal development
- follow the contours of the dermal papillae
- part of the papillary region of the dermis
Accessory structures of the skin
hair
skin glands
nails
Hair (define)
- found on most of body except palms and soles.
- contain small muscle (arrector pili muscle) causing goose bumps
Arrector Pili Muscle
cause hair to stand up/goosebumps
Skin glands (define)
Are epithelial cells that secrete a substance (ie sebaceous glands, sudoriferous glands, ceruminous glands)
Sebaceous glands
Produce oils
Sudoriferous glands
produce sweat (ie eccrine glands and apocrine glands)
Eccrine glands
Type of sweat gland: (most numerous) are found in most regions of
the body, found most regions of the body, especially the
forehead, palms and soles.
Apocrine gland
Type of sweat gland:have larger ducts and lumens and are mainly
found in the armpits, groin, areola of the breast and bearded
area of the face in adult males.
Ceruminous glands
modified sweat glands found in the ear and produce
cerumen (earwax)
Nails
plates of tightly packed, hard, dead, keratinized epidermal cells
Nail Body
visible part of the nail
Free edge (nail)
part of the nail plate that may extend past the distal end of the
finger
Nail root
portion of the nail that is buried in a fold of skin
Nail functions
Protect fingertips
Provide support and counterpressure to the fingers
Allow to hold/manipulate small objects
Used to scratch and groom
Deep wound healing
4 phases: inflammatory, migratory, proliferation, maturation
Inflammatory phase
(deep wound healing phase #1)
Blood clot forms and loosely unites the wound edges (inflammation is involved)
Migratory phase
(deep wound healing phase #2)
Clot becomes a scab
Epidermal cells migrate beneath the scab to fix the wound
Proliferation phase
(deep wound healing phase #3)
Extensive growth of epithelial cells under the scab
Formation of collagen fibers in random patterns
Continued growth of blood vessels
Maturation phase
(deep wound healing phase) The scab falls off once the skin has been restored
Fibrosis
process of scar tissue formation
Hypertrophic scar
scar tissue remains within the boundaries of the wound
Keloid scar
scar extends beyond the boundaries of the wound to the surrounding tissues
Age on skin
it gets thinner
Tinea
fungal infection (corporis, capitis, pedis, unguium, versicolor
Tinea corporis
fungal infection of the body better known as Ringworm
Tinea Capitis
fungal infection of the scalp
Tinea Pedis
Fungal infection of the foot (Athlete’s foot)
Tinea Unguium
fungal infection of the nail
Tinea Versicolor
Fungal infection that creates patches of yellow, pink or brown scaling
Acne
inflammation of the pilosebaceous unit of sebaceous glands
Psoriasis
- common/chronic skin disorder
- keratinocytes divide and move more quickly than normal from the stratum
basale to the stratum corneum - shed prematurely (7 to 10 days)
- immature keratinocytes make an abnormal keratin, which forms flaky,
silvery scales at the skin surface (knees, elbows, scalp)
Pruritis
Sensation of itch
Vitiligo
partial or complete loss of melanocytes from patches of skin that produce irregular white spots.
Impetigo
bacterial infection
Herpes Zoster
Characterized by lesions that are restricted to skin areas supplied by a single dorsal root ganglia
Stratum basale
is the deepest layer
o Also known as Stratum germinativum
Stratum spinosum
(Layer #2 from bottom of thick AND thin skin)
Consists numerous keratinocytes arranged in 8-10 layers
Stratum granulosum
(Layer #3 from the bottom for thick AND thin skin)
Consists of 3-5 layers of flattened keratinocytes undergoing apoptosis (programmed cell death)
Creates keratin
Creates the waterproof seal
Stratum lucidum
(Layer #4 from the bottom for thick skin)
thick skin ONLY
Only present in palms and soles of the hands and feet
Stratum corneum
(LAST or top layer for thick and thin skin)
25-30 layers of flattened dead keratinocytes
Keratinocytes
the most numerous (85%) and produce keratin that makes
skin tough and waterproof
Melanocytes
(8%) produce melanin which contributes to skin color
Macrophages
(Langerhans cells) participate in immune response
Tactile epithelial cells
(Merkel cells) are the least numerous and detect touch
