skin and fascia Flashcards
what layers can the skin be divided into?
epidermis (superficial )
dermis (deep connective tissue )
hypodermis (areolar and adipose , not part of the skin)
describe the dermis .
dense layer of irregular connective tissue (collagen and elastic fibers)
rich in nerves and blood vessels
contains hair follicles , arrestor pilli muscle and sebaceous gland which forms the pill sebaceous unit
what are cleavage lines ?
bundles of collagen and elastic fibers of the dermis that run longitudinally in the limbs and transverse in the trunk
lie within the reticular layer of dermis
which heal faster , incisions made parallel to cleavage lines or incisions made across them?
Incisions made parallel to these lines tend to gape less and heal more readily than incisions made across cleavage lines.
what are hair follicles invaginations of?
Hair follicles are tubular invaginations of epidermis.
what does the arrector pili smooth muscle connect ?
Arrector pili smooth muscle, connects the follicle to the superficial part of the dermis
what are sebaceous glands?
Are holocrine glands (cells of gland rupture during secretion).
Secrete sebum which prevent dryness
describe sweat glands.
Each gland is a single long tube, with highly coiled end while the body is the secretory part.
It is lined by cuboidal epithelium
(merocrine)
describe the superficial fascia
oose, mixture of adipose and loose areolar tissues.
It unites the skin to the underlying structures.
It is dense in some places as scalp, palm of hand and sole of foot and contains collagen bundles
It is thin in the eyelids, auricle, scrotum, penis and clitoris (devoid of adipose tissue).
describe the deep fascia.
It is more dense than superficial fascia
Collagenous bundles are more compact and more regularly arranged
It is usually present in the form of membranes
