Integumentary System Flashcards
Integumentary system is the largest system of the body (T/F)
T
Cutaneous membrane include:
epidermis, dermis
Accessory structures of the integumentary system:
Hair, nails, sweat glands, sebaceous glands, nerve fibers
________: consists of areolar (loose connective tissue) and adipose tissues; a place to store fat and contains large blood vessels that supply the skin; contains nerve endings (lamellated corpuscles) that are sensitive to pressure
Subcutaneous layer (hypodermis)
Functions of skin:
Protection of underlying tissues and organs, thermoregulation, blood reservoir, cutaneous sensations, excretion and absorption, storage of lipids, synthesis of vitamin D3
_____ is caused by Vitamin D3 deficiency, result
in bending of abnormally weak and flexible
bones
Rickets
_____ is essential for the absorption of
calcium and phosphorus in the small intestine
Calcitriol
UV light + steroid compound in skin → Vit D3 (cholecalciferol) and it is used to synthesize the hormone _____ by _____.
calcitriol, kidneys
______: 90% of epidermal cells; arrange in layers; produce ____ and ______
Keratinocyte, keratin, lamellar granules
______: 8% of the epidermal cells; produce pigment called
______
Melanocyte, melanin
______: a small fraction of epidermal cells; arise from red bone marrow and migrate to the epidermis, participate in immune responses; easily damaged by UV light
Langerhans cell
______: constitute the least % of
epidermal cells; located in the deepest layer of the epidermis; contact the flattened process of sensory neuron, which is called ___ disc to detect touch sensations
Merkel cell
______ is the process of newly formed cells in the stratum basale are slowly pushed to the surface. As cells move from one epithelial layer to the next, they accumulate more and more keratin.Eventually, the _____ cells slough off and are replaced by underlying cells
Keratinization, keratinized
_________ is unique for each individual; downward projections of the epidermis
into the dermis between dermal papillae of the papillary region; create a strong bond between dermis and epidermis; increase surface area of the epidermis (increase grip by increasing friction, increase the number of _____ of touch, thus increases ____ sensitivity)
Epidermal ridges, corpuscles, tactile
______:
* Essential to the survival of the epidermis
* Composed of dense irregular connective tissue containing collagen and elastic fibers
* Thicker than epidermis, thickness varies from region to region (thickness on palms and soles)
* Has the ability to stretch and recoil
* Blood vessels, nerves, glands, and hair follicles are embedded
* Divided into 2 layers based on its
tissue structure: __________
Dermis
papillary layer, reticular layer
_____ layer (in dermis)
* 1/5 of the thickness of the total layer
* Consists of thin collagen and fine elastic fibers
* Dermal papillae → increase surface by projecting into the surface of the epidermis
* Contain capillaries → support and nourish epidermis
* Free nerve endings (dendrites that lack apparent structural specialization) that initiate signals that give rise to sensations of warmth, coolness, pain, tickling and itching
papillary
_____ layer (in dermis)
* Attached to subcutaneous layer
* Consists of dense irregular connective tissue combining collagen and elastic fibers → provide skin with strength, the ability to stretch (extensibility) and the ability to return to original shape after stretching (elasticity)
* Spaces between fibers contain adipose cells, hair follicles, nerves, sebaceous glands, and sweat glands
reticular
Epidermal pigmentation
3 pigments:
Melanin, carotene, hemoglobin
Which pigment is produced by melanocytes; increase production by the exposure to ultraviolet light
Melanin
_____: a yellow-orange pigment that gives egg yolks and carrots
their colour; precursor of vitamin A; deposit in skin after eating large amount of ______-rich food
Carotene
Precursor of vitamin A is ______.
carotene
Skin colour ranges from pink to red depending on the ____ content of the blood moving through capillaries in the dermis. The red colour is due to _______, the oxygen-carrying pigment in red blood cells
oxygen, haemoglobin
Hair present on most skin surfaces except _______.
palms, soles, and plantar surface
of feet
____ and _____ influences determine the thickness and the pattern of hair distribution
Genetic, hormonal
Functions of hair:
Protects the scalp from injury
Protects the scalp from UV light
Decreases heat loss from the scalp
Senses light touch
(Touch receptors
associated with hair follicles are activated whenever a hair is moved even slightly)
_______: branched, rounded glands, which are connected to hair follicles (with few exceptions)
The secreting portion of the gland lies in the ____ and usually opens into the neck of a hair follicle
Sebaceous glands, dermis
In some locations, such as ___ and ________, sebaceous glands open directly onto the surface of the skin.
lips, tarsal glands of the eyelids
Sebaceous glands is absent in the ____ and _____.
palms, soles
Sebaceous glands is small in most area of the ____ and _____, while large in the skin of ____, ____, _____and _______
trunks, limbs
breast, face, neck, superior chest
Sebaceous glands secrete an oily substance called _____:
A mixture of ________; coats the surface of hairs → helps to keep hair from drying and brittle; prevents excessive evaporation of water from the skin; keep the skin soft and pliable; inhibit the growth of some bacteria
sebum, triglycerides, cholesterol, proteins and salts
Sweat glands are divided into 2 main types based on structure and type of secretion:
Eccrine (Merocrine) sweat glands (watery fluid onto the surface of skin)
Apocrine sweat gland (thick, odorous to hair follicles)
____:
Plates of tightly packed, hard, dead, _____ epidermal cells that form a clear, solid covering over the dorsal surfaces of the distal portions of the digits
Nail, keratinized
Each nail consists of a ___, a ___ and a ____.
nail body, free edge, nail root
The growth rate of nails is influenced by:
age, health, nutritional status
Functions of nail:
Protect the distal end of the digits.
Provide support and counterpressure to the palmar surface of the fingers to enhance touch perception and manipulation.
Allow us to grasp and manipulate small objects.
4 phases of skin repair
Inflammation phase, migration phase, proliferation phase, scarring phase
Lists types of burn injury
Scald, flame, chemical, electrical, contact, radiation, cold burn or friction burn
Burn injury destroy some of the skin’s
contribution to homeostasis, which
includes:
protect against microbial invasion, protect against dehydration, thermoregulation
Tissue damage is proportional to:
Temperature, nature of agent, length of time exposure, body part involved, age
Level of burn is graded according to the severity and depth of tissue involvement:
First degree burn, second degree burn, third degree burn
First degree burn:
only affect epidermis, mild pain, minimal tissue damage, heals 48-72 hours without scarring
Second degree burn:
affect epidermis and dermis, cherry red moist (Partial thickness), white, yellow or brown leathery (Full thickness) appearing, painful because sensation intact, painless in full thickness due to heat destruction of nerve endings, heal in 7-28 days with minimal scarring
Third degree burn:
epidermis, dermis and subcutaneous layer (full thickness burn), extends to tendon, muscle and bone, black charred appearance, may need amputation, escharotomy and fasciotomy
Assessment based on ___, and ____ of burn
A major burn includes:
depth, area
Third degree burn over 10% of the body surface area
Or Second degree burn over 25% of the body surface area
Or Third degree burns on face, hands, feet or perineum
When burn area exceed ___%, more than half of the victim die
70
A quick method for estimating the surface area
affected by a burn in an adult is the ‘______’
rule of nines
Rule of nines:
Head & neck- 4.5% + 4.5%
Upper limb- 9% + 9%
Front of trunk- 18%
Back of trunk- 18%
Lower limb- 18% + 18%
Perineum- 1%
Skin cancer may be cause by __________.
excessive exposure to ultraviolet radiation
3 common types of skin cancer:
Basal cell carcinomas, squamous cell carcinomas, malignant melanomas
Properties of basal cell carcinomas:
Tumor arise from cells in the stratum basale
Most common and rarely metastasize
Properties of squamous cell carcinomas:
Tumor arise from stratum spinosum
A variable tendency to metastasize
Property of malignant melanomas:
Metastasize rapidly and can kill a person within months of diagnosis.
Early warning signs of malignant melanomas:
Asymmetry – irregular shapes
Border – irregular border
Colour – uneven coloration
Diameter – ordinary moles typically smaller than 6mm
Evolving – change in size, shape and colour
