integumentary system: dermis and hypodermis Flashcards
what is the dermis mostly made up of?
connective tissue fibers
where are all blood vessels, nerves, sweat glands, and hair follicles found?
the dermis
what do collagen proteins do?
provides structural support
what do elastic fibers do?
provides extra elasticity to this layer
what do reticular fibers do?
forms a woven mesh to provide additional support
what does the more superficial half of the dermis contain?
blood vessels and nerves that help feed and bring in sensations from the epidermis
what is the deeper half of the dermis called?
reticular layer
does the reticular layer have a higher or lower concentration of fibrous materials?
higher concentration
in what way do collagen fibers in the reticular layer run? what do these lines create?
they run parallel to one another; lines of cleavage
what happens if a surgeon makes cuts along the lines of cleavage?
there is less scar tissue
what happens if a surgeon makes cuts perpendicular to the lines of cleavage?
they break the collagen fibers, pulling apart the wound, and making it more difficult for healing to occur
what do hair follicles do?
make hair
what do arrector pili do?
smooth muscles that can cause hairs to stand up when cold/scared (goosebumps)
what do sweat glands do?
produces sweat to help with thermoregulation
what do merocrine glands do and where are they located?
produces sweat that is watery, salty, and non-smelly; located everywhere
what do apocrine glands do and where are they located?
produces sweat that is milky, sticky, and smelly; located in the armpits, groin, and nipples
when do apocrine glands activate?
at puberty
where are sebaceous glands located?
found in the dermis near hair follicles
what do sebaceous glands produce? what does the thing they produce do?
produces an oil called sebum that is secreted onto the surface of the skin and helps keep the stratum corneum moisturized
what has anti-microbial properties?
sebum
what happens if sebaceous glands get clogged? (due to dirt, etc)
pimples/sebaceous cysts occur
what are the four functions of the hypodermis?
storing energy, connecting the dermis layer to your muscles and bones, insulating your body, and protecting your body from harm (cushioning)
what happens when the hypodermis thins?
skin aging
what is the hypodermis mainly made up of?
mostly connective tissues and adipocytes (fat cells)
what’s another name for fat cells?
adipocytes
