Integumentary System Flashcards
2 layers of the skin
epidermis and dermis
uppermost layer that prevents abrasion and water loss
epidermis
10-20 times thicker than the epidermis
dermis
function as padding and insulation and connects skin to underlying tissue or bone.
hypodermis/subcutaneous tissue
main cells of the epidermis
keratinocytes
made up of loose connective tissue
hypodermis/subcutaneous tissue
provides most of the skin’s structural strength
dermis
contains half of the body’s stored fat
hypodermis/subcutaneous tissue
consists of skin and accessory structures, such as hair, nails, and glands.
integumentary system
new keratinocytes form in the —– layer?
basal layer
made up of stratified squamous epithelium
epidermis
new keratinocytes are formed by
mitosis
process in which new cells push up older cells to the surface
keratinization
layers of the epidermis are called
strata
consists of a single layer of cuboidal cells that undergo mitosis.
stratum basale
layers of the epidermis
mostly consists of keratinocytes held together by sticky proteins called desmosomes
stratum spinosum
the stratum spinosum consists of keratinocytes that are held together by sticky proteins called
desmosomes
partly responsible for the skin’s strength and flexibility.
stratum spinosum
contains langerhans cells (epidermal immune cells)
stratum spinosum
where keratin is packaged in keratohyaline granules
stratum granulosum
the keratinocytes produce a lot of keratin in this layer
stratum granulosum
layers of the epidermis
the keratinocytes become flatter, more brittle, and lose their nuclei.
stratum granulosum
layers of the epidermis
keratinocytes produce lipids and nmf
stratum granulosum (natural moisturizing factor)
layers of the epidermis
once the keratinocytes leave the stratum granulosum they die and form the
stratum lucidum
thin transparent layer of keratinocytes
stratum lucidum
thin layer of cells can only be found in the thick skin on the palms an soles
stratum lucidum
25 or more dead squamous cells filled with keratin
stratum corneum
in this layer, keratinocytes become corneocytes
stratum corneum
the entire stratum corneum layer is replaced with new cells in a process known as
desquamation
made up of dense collagenous connective tissue
dermis
nerves, hair follicles, smooth muscles, glands and lymphatic vessels extend into the
dermis
collagen fibers of the dermis are oriented in many different locations called
cleavage or tension lines
skin is more resistant to stretch along these lines
cleavage or tension lines
______ and ______are responsible for the structural strength of the dermis
collagen and elastic fibers
an incision made _____ the cleavage lines can gap increasing time of healing and increase scar tissue
across
an incision made ______ to the cleavage lines result in less gapping and faster healing and less scar tissue
parallel
parallel curving ridges found in the hands soles foot tips of the digits that make up the finger prints
dermal papillae
dermis projections that extend towards the epidermis
dermal papillae
responsible for the skin, eyes, and hair pigments
melanin
melanin is produced by
melanocytes
golgi apparatus of the melanocytes package melanin into vesicles called
melanosomes
melanin pigment is transferred from melanocytes to the cytoplasm of keratinocytes through
phagocytosis
melanin production is determined by:
genetic factors, exposure to light, and hormones
a decrease in blood oxygen produces a bluish discoloration
cyanosis
congenital disorders of the blood dermis in the dermis
birthmarks
each hair arises from a
hair follicle
____ of the hair protrudes above the surface of the skin
shaft
below the surface
root
Parts of hair
expanded base of the root
hair bulb
associated with each hair follicle are smooth muscle cells. causes goose bumps
arrector pili muscle
two forms of melanin:
dominant pigment in brown and black hair
eumelanin
dominant pigment in red hair
pheomelanin
variety of textures caused by
condition of hair follicle
simple branched acinar glands which produce sebum mostly connected to the superficial part of the hair follicle.
sebaceous gland
sweat glands
suderiferous
coiled tubular glands that produce sweat
suderiferous/sweat glands
2 types of sweat glands
produce secretion directly open to the skin through sweat pores
eccrine sweat glands
produce thick secretion. open into the hair follicles only in the armpit and genitalia.
apocrine sweat glands
a thin plate consisting of dead stratum corneum cells; very hard type of keratin
nails
nails grow___
continuously and does not have a resting stage
5 major functions of the integumentary system
protection
sensation
vitamin D
temperature regulation
excretion
results in increased blood flow, increased heat loss
blood vessel dilation
decreased blood flow, decreased heat loss
blood vessel constriction
injury to the tissue caused by heat, friction, cold, chemicals, electricity, or by radiation.
burns
most common type of cancer; associated with exposure to UV light from the sun
skin cancer
most frequent type of skin cancer. begins in stratum basale then rises up into dermis to produce an open ulcer.
basal cell carcinoma
develops immediately superficial o the stratum basale. nodular, keratinized tumor confined to the epidermis
squamous cell carcinoma
rare form of skin cancer. arises from melanocytes, in a preexisting mole
malignant melanoma
Sensation:
touch
merkel’s disc
sensitive touch
Meissner’s corpuscle
sensation
Ruffini’s copuscle
touch and pressure
sensation
free nerve ending
pain and temperature
sensation
cold receptors
Krause’s corpuscles
sensation
pacinian corpuscle
pressure
