Integumentary System Part III Flashcards
located between the epidermis and subcutaneous layer
DERMIS
anchors epidermal accessory structures (e.g., hair follicles, sweat glands)
DERMIS
TWO COMPONENTS OF THE DERMIS
- PAPILLARY LAYER
- RETICULAR LAYER
to support the avascular epidermis with vital nutrients
PAPILLARY LAYER
to provide a network for thermoregulation.
PAPILLARY LAYER
Contains free sensory nerve endings, smaller capillaries, lymphatics, and structures such as Meissner’s corpuscles [mechanoreceptor] (responsible for light touch)
PAPILLARY LAYER
consists of dense irregular connective tissue
RETICULAR LAYER
is important in giving the skin its overall strength and elasticity
RETICULAR LAYER
Housing other important epithelial-derived structures such as glands and hair follicles.
RETICULAR LAYER
Contains larger blood vessels and nerve fibers.
RETICULAR LAYER
Lies below the integument
HYPODERMIS
Stabilizes the skin
HYPODERMIS
Allows separate movement
HYPODERMIS
Made of elastic areolar and adipose tissues
HYPODERMIS
Connected to the reticular layer of the intergument by connective tissue fibers
HYPODERMIS
Deposits of Subcutaneous fats:
- Distribution patterns determined by hormones
- Reduced by cosmetic liposuction (lipoplasty).
ACCESSORY STRUCTURES
- Hair follicles and hair
- Sebaceous glands
- Nails
- Sweat glands
Produced by hair follicles which are made of hard keratinized epithelial cells.
HAIR
Provide pigment for hair color
MELANOCYTES
the organs that form the hairs
HAIR FOLLICLES
wrapped in a dense connective tissue sheath
HAIR FOLLICLES
base is surrounded by sensory nerves (Root Hair Plexus)
HAIR FOLLICLES
Controls bacteria
HAIR FOLLICLES
ACCESSORY STRUCTURES OF HAIR:
ARRECTOR PILI
SEBACEOUS
PILOSEBACEOUS UNIT
involuntary smooth muscle
ARRECTOR PILI
causes hair to stand up
ARRECTOR PILI
produces “goosebumps”
ARRECTOR PILI
lubricates the hair
SEBACEOUS
branched acinar glands
SEBACEOUS
is made of hair follicle and its associated sebaceous glands
PILOSEBACEOUS UNIT
REGIONS OF THE HAIR:
HAIR ROOT
HAIR SHAFT
lower part of the hair
HAIR ROOT
attached to the integument
HAIR ROOT
upper part of the hair
HAIR SHAFT
not attached to the integument
HAIR SHAFT
HAIR SHAFT STRUCTURE:
MEDULLA
CORTEX
CUTICLE
Core, dead cells contain soft keratin and air to provide flexible
MEDULLA
middle layer, dead cells contain hard keratin to provide stiffness
CORTEX
eponychium
CUTICLE
outermost, overlapping dead keratinized cells form shiny surface.
CUTICLE
protect fingers and toes
NAILS
made of dead cells packed with keratin
NAILS
______ can change nail structure.
Metabolic disorders
occurs in a deep epidermal fold near the bone called the nail root
NAIL PRODUCTION
STRUCTURES OF A NAIL:
NAIL BODY
LUNULA
HYPONYCHIUM
nail plate
NAIL BODY
the visible portion of the nail
NAIL BODY
covers the nail bed
NAIL BODY
the pail crescent at the base of the nail
LUNULA
epidermal fold at the distal end of the finger
HYPONYCHIUM
SWEAT GLANDS:
ECCRINE SWEAT GLANDS
APOCRINE SWEAT GLAND
merocrine secretion
ECCRINE SWEAT GLANDS
empty directly onto skin surface
ECCRINE SWEAT GLANDS
Clear, watery secretion (99% H2O; rest NaCl + some waste products)
ECCRINE SWEAT GLANDS
Location: most all over the body (esp. abundant on palms & soles of the feet 500/cm2)
ECCRINE SWEAT GLANDS
empty into hair follicle
APOCRINE SWEAT GLAND
viscous, cloudy secretion > good nutrient source for bacteria (odor)
APOCRINE SWEAT GLAND
secretion may contain Pheromones
APOCRINE SWEAT GLAND
secretion begins at puberty and is stimulated during emotional distress
APOCRINE SWEAT GLAND
Location of Apocrine Sweat Glands
armpits, groin, nipples