Chapter 7 Flashcards
is considered an organ system because of the multiple organs, the skin, and the accessory organs
integument
function is to protect and insulate
skin
the ____ ____ plays an important role in temperature regulation by regulating heat loss from the body surface
capillary network
skin can also act as an ___ ____
excretory system
region of skin composed of epithelium; top
epidermis
region of skin with the an underlying connective tissue; middle layer
dermis
not considered part of the skin, deep to the dermis, primarily adipose tissue
hypodermis
the epidermis is ____
avascular
the avascular epidermis is a ___ ___ ____ ___
keratinized stratified squamous epithelium
the most abundant epidermal cell, main function is to produce keratin fibrils
keratinocytes
is a fibrous protein that gives the epidermis its durability and protective capabilities
keratin
spidery black cells that produce the brown-to-black pigment called melanin
melanocytes
brown-to-black pigment
melanin
cells arise from the bone marrow and migrate to the epidermis; key role in immune response
dendritic cells
occasional spiky hemispheres that form sensitive touch receptors located at the epidermal-dermal junction
tactile epithelial cells
there are __ layers of epidermis
four
outermost layer of the epidermis consisting of 20-30 layers of dead keratinocytes; constantly being exfoliated and replaced by the division of deeper cells
stratum coreneum
stratum coreneum is also called the
horny layer
present only in thick skin, a very transparent band of flattened dead keratinocytes with indistinct boundaries
stratum lucidum
stratum lucidum is also called the
clear layer
thin layer with abundant granules
stratum granulosum
stratum granulosum is also called the
granular layer
type of granule that contain a waterproofing glycolipid that is secreted into the extracellular space
lamellar granules
type of granule that helps form keratin in the more superficial layers
keratohyaline granules
several layers of cells that contain thick, weblike bundles of intermediate filaments made of pre-keratin protein
stratum spinosum
the stratum spinosum is also called the
spiny layer
a single row of cells immediately abode the dermis; these cells are constantly undergoing mitosis
stratum basale
the stratum basale layer is also called the
basal layer
in order from deep to superficial the layers of the epidermis are the
stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum
the dermis is made from
connective tissue proper
the dermis consists of ___ principle regions
two
the more superficial dermal region composed of areolar connective tissue with dermal papillae, capillary networks, pain receptors, and touch receptors
papillary dermis
fingerlike projections that lie on top of larger dermal ridges; produce fingerprints
dermal papillae
deepest skin layer that is composed of dense irregular connective tissue and contains many arteries and veins, sweat and sebaceous glands, and pressure receptors
reticular dermis
the dermis layer plays a role in regulation of __ _____
body temperature
the dermis is full of ___ ____ and ___ fibers
lymphatic vessels; nerve
is a result of the relative amount of melanin in the skin, the relative amount of carotene in the skin, and the degree of oxygenation in the blood
skin color
a yellow-orange pigment
carotene
a blueish cast due to inadequately oxygenated blood
cyanosis
the tissues become yellowed
jaundice
bronzing of skin usually hints at
addison’s disease
accessory organs of the skin include
cutaneous glands, hair, and nails
hornlike derivatives of the epidermis
nails
part of the nail that is the visible attached portion
nail plate
the portion of the nail that grows out away from the body
free edge
the region beneath the free edge of the nail
hyponychium
the part that is embedded in the skin and adheres to an epithelial nail bed
nail root
skin folds that overlap the borders of the nail
nail folds
projection of the thick proximal nail fold commonly called the cuticle
eponychium
extension of the stratum basale beneath the nail
nail bed
the thickened proximal part of the nail bed containing germinal cells responsible for nail growth
nail matrix
the proximal region of the thickened nail matrix which appears as a white crescent moon
lunule
structure formed from both epidermal and dermal cells
hair follicle
is enclosed by a thickened basement membrane and a peripheral connective tissue sheath
epithelial root sheath
essentially dermal tissue
peripheral connective tissue sheath
small nipple of dermal tissue protrudes into the hair bulb from the peripheral connective tissue sheath and provide nutrition to the growing hair
hair papilla
a layer of actively dividing epithelial cells located on top of the hair papilla
hair matrix
small bands of smooth muscle cells connect to each hair follicle to the papillary layer of the dermis
arrector pili muscle
cause hair to stand upright when cold or frightened
arrector pili muscle
found nearly all over the skin, their ducts empty into a hair follicle or on the skins surface
sebaceous (oil) glands
is the product of sebaceous glands; mixture of oily substances and fragmented cells that act as a lubricant
sebum
the sebaceous glands become more oily during
puberty
are accumulations of dried sebum, bacteria, and melanin from epithelial cells in the oil duct
blackheads
is an active infection of the sebaceous glands
acne
are exocrine glands that have pores
sweat (sudoriferous) glands
have two categories the sebaceous gland and the sweat glands
cutaneous glands
glands distributed all over the body that produce clear secretion consisting of water, salts, and urea
eccrine sweat glands
found predominately in the axillary and genital areas; secrete the basic components of eccrine sweat plus proteins and fat rich substances; odorless until bacteria break down its components
apocrine sweat glands
