Ch.6 Flashcards
The skin, as an organ, is also referred to as the
cutaneous membrane
Integumentary system includes
Skin, hair, nails, sweat glands, sebaceous glands
What are intradermal injections
administered into the dermis
What happens to keratinocytes as they are pushed from the deeper layers of the epidermis towards the surface?
They die
What tissue type forms most of the dermis?
dense, irregular connective
Nerve fibers scattered throughout the dermis are associated with what structures?
muscle, gland, sensory receptors
What are dermal papillae
projections of dermal tissue
The blank is thicker than the blank
dermis; epidermis
Melanin is confined to what area of the skin?
epidermis
Why does exposure to ultraviolet light darken the skin?
stimulates synthesis of melanin
What epidermal layer consists of a single layer of columnar cells that undergo mitosis?
stratum basale
What determines color of the skin?
amount of melanin
The subcutaneous layer is made up of what tissue types?
aureola and adipose
Blood vessels from what layer supply epidermal cells with nutrients?
dermis
Skin plays an important role in production what vitamin?
D
Dark hair is due to having more what?
eumelanin
Arrector pili muscles are attached to what feature of the skin?
hair follicles
What is secreted by sebaceous glands?
sebum (oils)
Where are apocrine sweat glands most abundant?
axillae and groin
How do merocrine sweat glands differ from sebaceous glands?
sebaceous has oil, merocrine water, sweaty
Type of glands secrete breast milk and ear wax
specialized glands
Primary means of body heat loss
radiation
What is normal response to excessive loss of body heat in a cold environment
dermal blood vessels constricting; shivering
Sweating results in loss of body heat by what means
evaporation
What is convection
heat loss due to circulating air currents
As body temp increases, the dermal blood vessels are stillmulated to what
dilate
The homeostatic mechanism that maintains body temp has what as its control center
hypothalamus
How can the body generate heat when one gets chilled
increase skeletal muscle activity
As a person ages, what happens to their skin
thins, loses fat, wrinkles
Why do elderly have more difficulty maintaining a stable body temp
decrease in fat below skin, decrease sweat glands
What change to the skin would cause wrinkles to occur during aging
reduced elastin and collagen, dermis smaller
Basement membrane separates what
epidermis from dermis
The blank of the blank layer is important in conserving body heat
adipose ; subcutaneous
What cell type can lead to cutaneous melanomas
melanocytes
Superficial layer of epidermal cells are what shape
squamous
What epidermal cell type responds to light touch by stimulating sensory nerve endings
tactile
Exposure to ultraviolet radiation increases the risk of developing what
skin cance
What feature of the skin gives it elasticity and toughness
connective tissue in dermis
Feature of skin that is involved in acne
sebaceous glands
Why does the elevated body temp seen with a fever develop
set point for body temp becomes elevated
What is the largest organs of the body by weight
skin
what condition results from a complete lack of melanin
ablinism
As keratinocytes age, and are pushed further away from dermis, they develop _____ which help fasten the cells tightly tog.
desmosomes
Granules called _____ serve to transfer pigment from melanocytes to nearby keratinocytes
melanosomes
What is the cause of cyanosis
low blood oxygen levels
You step out of the shower and vigorously rub your skin w/ a towel. If you were able to analyze the towel, you would find skin cells. They are most likely what type of cell?
keratincytes
Layer of epidermis that is absent from the skin
stratum lucidum
Water loss from the skin is minimal because of the structure of the ____
epidermis
Order of epidermal strata, from superficial to deep
stratum corner, stratum lucid, stratum granulosum, stratum sponosum, stratum basale
What is keratin and what does it do
protein; waterproofs the skin
Structures within the skin, called accessory structures, originate from what?
epidermis
What cell type produces the nail plates?
specialized epithelial cells
Nail plate and bed relationship/location
plate lies in the nail bed
What gives nails their hardness
keratin cells
What forms the shafts of hair?
dead epidermal cells
Why might a
