Ch 5: Skin
The _________________ is the largest system of the body
-Sixteen percent of body weight
The integument is made up of two parts ________________ and ___________________.
Cutaneous membrane (skin)
_________________ originate in the dermis and extend through the epidermis to skin surface. Includes Hair, Nails, and Multicellular exocrine glands
Functions of ___________ are Protection of underlying tissues and organs; Excretion of salts, water, and organic wastes (glands); Maintenance of body temperature (insulation and evaporation); Production of melanin
Functions of _________:
Production of keratin
Synthesis of vitamin D3
Storage of lipids
Detection of touch, pressure, pain, and temperature
_______________________ has sensory receptors that detect touch, pressure, pain, vibration, and temperature. Blood vessels assist in thermoregulation.
The ________________ is avascular stratified squamous epithelium. Nutrients and oxygen diffuse from capillaries in the dermis
__________________ Contain large amounts of keratin and
Are the most abundant cells in the epidermis
_________________ is keratinocytes produce keratohyalin and keratin; Keratin fibers develop as cells become thinner and flatter; Gradually the plasma membranes thicken, the organelles disintegrate, and the cells die
Stratum Basale is attached to basement membrane by _______________________.
Stratum Basale forms epidermal ridges which are the basis of _______________.
______________ are tiny mounds that increase the area of basement membrane and strengthen attachment between epidermis and dermis
Stratum Basale has many basal cells, or ___________________.
Specialized Cells of Stratum Basale are ______________ and _________________.
merkel cells and melanocytes
_____________ found in hairless skin and responds to touch (trigger nervous system)
____________________ contain the pigment melanin and are scattered throughout stratum basale
_________________ — the “spiny layer” produced by division of stratum
basale; Eight to ten layers of keratinocytes bound by desmosomes;
Cells shrink until cytoskeletons stick out (spiny)
Continue to divide, increasing thickness of epithelium
Contain dendritic (Langerhans) cells, active in immune response
___________________ is the “grainy layer” that stops dividing, starts producing: Keratin and Keratohyalin
______________ is a tough, fibrous protein that makes up hair and nails
______________ are dense granules that Cross-link keratin fibers
Cells of ______________________ produce protein fibers, dehydrate and die, create tightly interlocked layer of keratin surrounded by keratohyalin
_________________ is the “clear layer” and found only in thick skin. It covers the stratum granulosum
_______________ is the “horn layer” that is exposed surface of skin; 15 to 30 layers of keratinized cells; Water resistant; Shed and replaced every two weeks
_________________ is the formation of a layer of dead, protective cells filled with keratin; Occurs on all exposed skin surfaces except eyes. Skin life cycle: It takes 7 to 10 days for a cell to move from stratum basale to stratum corneum
__________________ interstitial fluid lost by evaporation through the stratum corneum
______________ results from immersion in hypertonic solution (e.g., seawater [osmosis])
______________ results from immersion in hypotonic solution (e.g., freshwater [osmosis]) Causes swelling of epithelial cells, evident on the palms and soles
Skin Color Is Influenced by Two Pigments: ____________ and ______________ and Blood circulation (red blood cells)
Carotene and Melanin
_______________ is orange-yellow pigment that is found in orange vegetables and accumulates in epidermal cells and fatty tissues of the dermis. It can be converted to vitamin A.
___________ is yellow-brown or black pigment produced by melanocytes in stratum basale. Stored in transport vesicles (melanosomes) and transferred to keratinocytes
________________ produce and store melanin
Skin color depends on ___________ production, not number of melanocytes
Blood vessels _______ from heat, skin reddens.
Blood flow decreases, skin pales
____________ is bluish skin tint caused by severe reduction in blood flow or oxygenation
Pituitary tumor is excess _______.
Addison’s disease is disease of the pituitary gland that
__________ is loss of melanocytes and loss of color
Liver and kidneys convert vitamin D3 into _____________
Aids absorption of calcium and phosphorus
_____________________ is produced by glands (salivary and duodenum)
Epidermal Growth Factor (EGF)
Epidermal Growth Factor (EGF) is used in laboratories to grow __________________.
Functions of _______:
Promotes division of germinative cells
Accelerates keratin production
Stimulates epidermal repair
Stimulates glandular secretion
The ________________ consists of areolar tissue; Contains smaller capillaries, lymphatics, and sensory neurons; and has dermal papillae projecting between epidermal ridges
The __________________ consists of dense irregular connective tissue; contains larger blood vessels, lymphatic vessels, and nerve fibers; Contains collagen and elastic fibers; Contains connective tissue proper
________________ an inflammation of the papillary layer; Caused by infection, radiation, mechanical irritation, or chemicals (e.g., poison ivy); characterized by itch or pain
Another name for the eponychium is ______________.
__________________ are very strong, resist stretching but bend easily and provide flexibility
_________________ permit stretching and then recoil to original length and limit the flexibility of collagen fibers to prevent damage to tissue
_________________ is a network of arteries along the reticular layer
______________ is a capillary network from small arteries in papillary layer
_______________ is a capillary return deep to the papillary plexus
______________ is damage to blood vessels resulting in “black-and-blue” bruising
Functions of ____________:
Protects and insulates
Guards openings against particles and insects
Is sensitive to very light touch
The base of a hair follicle is surrounded by sensory nerves called ___________________.
root hair plexus
_________________ lubricate the hair and control bacteria
The ______________ produces hair matrix:
A layer of dividing basal cells
Produces hair structure
Pushes hair up and out of skin
In the Hair Shaft Structure the _____________ is the central core.
in the Hair Shaft Structure the ____________ is the surface layer.
In the Hair Shaft Structure the _____________ is the middle layer.
Medulla contains ____________ keratin
Cortex and cuticle contain _______________ keratin
____________ is not growing and is attached to an inactive follicle
_____________ is soft, fine and covers body surface
________________ is heavy, pigmented hair on Head, eyebrows, eyelashes and other parts of body after puberty
_________________ discharge directly onto skin surface
_____________________ are found in armpits, around nipples, and groin and secrete products into hair follicles. They produce sticky, cloudy secretions and break down and cause odors
Apocrine Sweat Glands
Apocrine Sweat Glands are surrounded by _________________.
They squeeze apocrine gland secretions onto skin surface in response to hormonal or nervous signal.
_____________________ are widely distributed on body surface,
especially on palms and soles. They are coiled, tubular
that discharge directly onto skin surface
Merocrine (Eccrine) Sweat Glands
____________ sweat glands discharge a watery fluid onto the surface of the skin.
__________________ glands produce cerumen (earwax) that protect the eardrum.
Autonomic nervous system (ANS) controls ______________ and ___________ sweat glands that work simultaneously over entire body.
sebaceous and apocrine
_____________ sweat glands are controlled independently and sweating occurs locally.
Nail production occurs in a deep epidermal fold near the bone called the ____________
Nail body the visible portion of the nail covers the ____________.
______________ is the pale crescent at the base of the nail
Skin beneath the distal free edge of the nail is the __________________.
hyponychium (onyx = nail)
________________ is the cuticle.
____________________ feels pressure or vibrations in the skin.
Lamellated (pacinian) corpuscle
Basal cell carcinoma begins in the ______________— a type of cell within the skin that produces new skin cells as old ones die off.
_______________ is the layer that are eight to ten layers of keratinocytes bound by desmosomes. Contain dendritic (Langerhans) cells, active in immune response.
The ________________ layer is a thinner and flatter where the cells start to die.
The thickest layer of epidermis is the __________________.
_____________ is caused by a deficiency in calcium and vitamin D.
______________ is when there is excess MSH (Melanocyte-stimulating hormone) which causes the skin to turn dark.
_________________ causes you to turn darker without sunlight.
- A disease of the pituitary gland