integumentary--- layers of the integument Flashcards
what does the integument consists of
dermal or cutaneous layer
and a subcutaneous or hypodermal layer
the dermal layers consists if how many sub-layers
2
what are the 2 sub-layers of the dermal layers
dermis and epidermis
what is the hypodermis (subcutaneous layer)
lowermost or deeper layer of the integument
what does the hypodermis or the subcutaneous layer consist of
primarily loose adipose connective tissue
blood vessels
lymphatic vessels
nerves
the hypodermis provides a transitional connective zone between what
overlying dermal layer and adjacent underlying body contents
what are the overlying dermal layer and adjacent body contents that the hypodermis provides a transitional connective zone between
outer skeletal muscle layers— some bony areas- particularly over the knee and elbow joint and the anterior surfaces of the lower leg (shins)
what is the dermis
middle layer of the 3 major integument layers
what is the dermis composed of
3 primary cell types – fibroblasts, macrophages, and adipocytes
what are the 2 sublayers of the dermis
reticular layer and papillary layer
what is the dermal reticular layer
roots of hair follicles, sweat glands, sebaceous glands, and sensory receptors are implanted within the reticular layer of the dermis
what is the dermal papillary layer
second sublayer of the dermis
what is the dermal papillary layer superior to
reticular layer
what does the papillary later consist of
areolar connective tissue
what does the areolar connective tissue of the papillary layer allow
allow substances to readily diffuse through the tissue
what is the epidermis
most superficial layer of the integument
what does the epidermis not have
direct blood supply
because the epidermis has no direct supply what does it depend on
diffusion
what does the epidermis depend on diffusion for
supplies of oxygen and nutrients
transport of CO2
other waste products
where does the epidermis begin
immediately adjacent to the superficial surface of the papillary layer of the dermis
how are the papillary layer and the epidermis separated
basement membrane
what is the basement layer
common feature of almost all epithelial tissues —serves as attachment surface for lowermost layers of epithelial cells
what additional function does the basement membrane have
immune system functions and cellular repair functions
what are the glands of the integument
sebaceous, sudoriferous, and ceruminous glands
how do exocrine glands secrete substances
glandular duct(tube) onto the surface of epithelial tissue—
where do the exocrine glands secrete substances by the grandular duct
either on the surface of the skin or luminal surface of epithelial lined hollow organ
what is an example of an epithelial lined hollow organ
small intestine
where do endocrine glands secrete substances
directly into the bloodstream or lymphatic system
where are sebaceous glands widely distributed
throughout the integument
where are sebaceous glands NOT widely distributed
soles of the feet and the palms of the hands
sebaceous glands have ducts that most commonly communicate with what
hair follicles
^^^but only a small percentage open directly onto the external epidermal surface
what does the sebaceous glands synthesize and secrete
sebum
what is sebum
oily or waxy substance that provides an oily medium
what does sebum contribute to
composition of the sweat layer on the surface of the skin
what does the oil component of sweat extends
extends cooling effects of evaporative sweating
what does sebum prevent
dehydration
how does sebum prevent dehydration
by increasing the adherence of the sweat layer to the surface on the skin
what does sebum strongly inhibits
inhibits the growth of potentially harmful microorganisms
what are Sudoriferous Glands
type of sweat glands– there are two types
what are the 2 types of sudoriferous glands
eccrine and apocrine glands
where are eccrine glands found
found all over the body
what does the eccrine glands secrete and what does it do
secretes a watery product to cool the skin
where are apocrine glands found
in the armpits and perianal area
what do apocrine glands do
secrete a vicious and odorous product
where are ceruminous glands found
human external auditory canal (ear)
what are ceruminous glands
modified apocrine glands
what does the ceruminous glands do
work with apocrine glands to produce a cerumen— earwax
