Integumentary System Flashcards
what are the three appendages
hair, nails, glands
what are the functions of appendages
protection temperature regulation sensory organs metabolic functions blood reservoir excretion
the thin outer layer of skin is called
epidermis
the deep thick layer of skin consisting of connective tissue and blood vessels is called
Dermis
the layers of epidermis
stratum basale (deepest) stratum granulosum (middle) stratum corneum (closest to the top)
the layers of dermis
1.dense irregular connective tissue
gives the skin toughness + ability to stretch
2.blood vessels
regulates blood flow and brings nutrients to cells
3.sensory receptors
detects heat, cold, pressure, pain
4.hair follicles, sweat/oil glands
temp regulation, blood reservoir, sensation
functions of hair
air filtration, sensation of touch
functions of nails
protection, manipulation
functions of sudoriferous (sweat) glands
excretion
temp regulation
protection
functions of sebaceous (oil) glands
protection
barrier
what are sebaceous glands
located at hair follicles, secretes sebum, keeps skin moist to prevent drying and cracking, stops water from leaving skin, contains anti bacterial substances
what are sudoriferous glands
secretes sweat,
eliminates nitrogen-containing substances,
cools the body by sweat evaporation,
contains anti bacterial substances
what is the epidermis layer
thin outer layer of skin, made of stratified squamous epithelium,
what is the dermis layer
the layer under epidermis, thicker, made of connective tissues, contains blood vessels
what is the subcutaneous layer
the layer under the dermis, made of areolar connective and adipose tissues,
what are the functions of the subcutaneous tissue
stores fat to insulate from heat loss and absorbs physical bumps, and anchors the skin to structures underneath
what is the stratum basale
stem cells in this layer undergo mitosis to replace dead epidermal cells + repair injuries,
stem cells produce keratinocytes to provide protection and produce vitamin D,
they will also produce melanocytes which produces dark pigment to protect from UV
what are the functions of the stratum basale
protection,
metabolism
melanocytes are responsible for what
macules and freckles,
vitiligo,
albinism
what is the stratum granulosum
the keratinocytes begin their differentiation,
cytoplasm begins to fill with the protein keratin, organelles begin to break down,
lamellar granules form in the cells,
tight junctions attach the cells together
what is the stratum corneum
keratinocytes have fully differentiated,
forms a waterproof layer,
forms a protective barrier against physical injury + foreign cells
how does hair work
grows from a small group of cells called hair papilla located in the dermis, grows out of a tube of cells crossing the dermis and epidermis called a hair follicle, they consist of dead keratinized cells, made of hard keratin cells
what’s a nail plate
made of epidermal cells produced by the nail matrix, become plate like and hard because they fill with hard keratin
what’s the nail root
covered by the cuticle
