Chapter 4- Integumentary System Flashcards
Epidermal cell types
keratinocytes, melanocytes, langerhan cells, Merkel cells
cells that produce keratin and provide protection
keratinocytes
cells that produce melanin
melanocytes
cells from bone marrow and are apart of the immune response
Langerhan cells
cells that are in the deepest layer. form touch receptor with sensory neuron
Merkel cells
process of keratinization
- stem cells divide and produce keratinocytes at basal lamina
- keratinocytes pushed to surface– fill with keratin and begin to due
- removed from outer layer if in contact with abrasion
layer of epidermis (5)
- stratum germinativum (bottom)
- stratum spinosum
- stratum granulosum
- stratum lucidum (not present in thin skin layer)
- stratum corneum (top)
deepest layer of cells– combo of merkel cells, melanocytes, keratinocytes, and stem cells that divide repeatedly
stratum germinativum
how are cells in stratum germinativum attached to each other and the basal lamina?
desmosomes and hemidesmosomes
8- 10 cell layer held together by dermosomes. melanin taken in by phagocytosis from nearby melanocytes
stratum spinosum
3-5 layer of flat dying cells. show nucelar degeneration. contain dark-staining keratohyalin granules
stratum granulosum
seen in thick skin on palms and soles of feet. 3-5 layers of clear, flat, dead cells–not stained anymore
stratum lucidum
25-30 layers of flat dead cells filled with keratin and surrounded by lipids. continuously shed. barrier to light, heat, water, chemicals and bacteria. friction stimulate callus formation
stratum corneum
found on palmar and plantar surfaces. about 30 layers of stratum corneum. contains all 5 layers of skin
thick skin
skin found on the rest of the body surfaces. has few layers of stratum corneum– does not have stratum lucidum
thin skin
produced in epidermis by melanocytes
melanin
type of melanin– typical brown or black
eumelanin
type of melanin– red-brown
pheomelanin
skin pigment– yellow orange pigment that is found in stratum croneum and subcutaneous
carotene
skin pigment- red, oxygenated pigment in blood cells
hemoglobin
part of the cutaneous membrane; composed of two layers– papillary layer and reticular layer
dermis
layer found within the dermis- composed of areolar CT. job is to connect the epidermis to the lower layers of the dermis. contain neurons and capillaries for nutrients to be carried to the dermis. contain dermal papillae
papillary layer
layer found within the dermis– anchors the skin to the rest of the body. contains large vessels, nerves, adipocytes, arrector pill muscle. composed of dense irregular CT
reticular layer
blood supplied to skin through 2 processes
cutaneous plexus and papillary plexus
network of arteries and veins supplying skin with blood. found in the subcutaneous layer
cutaneous plexus
follows epidermal and dermal boundary. helps nourish epidermal layer
papillary plexus
also known as superficial fascia//subcutaneous layer. consists of areolar CT and adipose CT. made up of collagen and elastic fibers. has no distinct boundry with the dermis. acts as insulator and stabilizer of the skin
hypodermis
found on surfaces except for hands, feet, fingers, lips, and eyeballs. 3 different types. varies on body location, age and gender
hair
3 types of hair
vellus, terminal, intermediate
type of hair– thinest known as peach fuzz
vellus hair
type of hair– thicker with darker pigment. mainly found on the head
terminal hair
type of hair– found on the arms. not too thick and not too thin
intermediate hair
what parts does the hair consist of
shaft, root and bulb. cuticle, cortex, medulla
hair growth stages
anagen stage, catagen stage, telogen stage
hair growth stage that last up to 6 years depending on the body part. matrix cells at the base of hair root producing length
anagen stage
hair growth stage that last up to 2 weeks. matrix cells inactive and follicle atrophies
catagen stage
hair growth stage when hair follicle remains dormant.. hair is eventually pushed out by new hair as cycle renews
telogen stage
glands of the skin
sebaceous, sudoriferous, ceruminous, mammary
oil glands. secrete sebum by holocine secretion.
sebaceous glands
sweat glands. coiled tubular gland. under neutral control. two types– apocrine and merocine
sudoriferous glands
use merocrine system of exocrine secretion– on most body surfaces– greatest on palm. involves sensible perspiration. function: cooling and protection
sudoriferous -merocrine sweat glans
uses merocrine system of exocrine secretions. associated with the hair follicle. located on axillae, areolae, groin. produces viscous secretion starting at puberty. function: reduce friction, cooling,secrete pheromones
sudoriferous- apocrine sweat glands
modified apocrine gland– milk production
mammary
modified apocrine gland– in external ear. secretion mixes with sebum to create ear wax
ceruminous
keratinized plate-like structure
nail
surface of skin that covers nail body
nail bed
source of nail production
nail root
whitish, half moon region at base of nail plate due to obscured blood vessels
lunula
tissue damage and cell death caused by heat, electricity, UV radiation or chemicals
burns
associated dangers with burns
dehydration, electrolyte imbalance, circulatory shock
type of burn; skin red and swollen– only epidermis damaged
first degree burn
type of burn; skin red with blisters– epidermis and upper dermis damaged
second degree burn
type of burn; gray, white or black– destroys entire layer
thrid degree burn
