Human Anatomy 4
A burn that destroys only the superficial cells of the epidermis, such as a mild sunburn, is classified as
first-degree
Which is the most logical reason for an elderly person's higher potential to be prone to skin infections, compared to a younger person?
stem cell activity in the epidermis declines in the elderly
A small amount of ultraviolet radiation is beneficial because it ________.
stimulates vitamin D3 synthesis in the epidermis
The deepest layer of cells in the epidermis is the cells of the ________.
stratum basale
The layer of the epidermis at the exposed surface is the
stratum corneum
When a person becomes "pale," what is the physiologic basis?
the blood supply to the skin decreases
Melanin serves to protect cells in the deeper layers of the epidermis from ________.
ultraviolet radiation
When the arrector pili muscles contract,
"goose bumps" are formed
Why are injections administered in the hypodermis when administering drugs using a hypodermic needle?
There is an abundance of capillaries in the hypodermis.
A "rug burn," which scrapes the skin, is an example of a(n)
abrasion
The condition that results from clogged sebaceous glands is
acne
The glands that begin discharging a sticky, cloudy, and potentially odorous secretion at puberty are called ________ glands.
apocrine
Merocrine sweat glands
are most common in the axillary and inguinal regions of the body
Which of the following conditions is the most common form of skin cancer?
basal cell carcinoma
The nail ________ covers the nail bed.
body
Nerve fibers in the dermis most likely function in
controlling blood flow to the dermis and epidermis
The blood supply to the skin arises from a network of blood vessels called the ________ plexus in the hypodermis, at its border with the reticular layer of the dermis.*
cutaneous
The fold of stratum corneum over the base of a nail is called the
cuticle
Shafts of hair are comprised of*
dead, keratinized epidermal cells
Epidermal cells are supplied with nutrients from blood vessels in the
dermis
The highly vascular layer of the skin, which provides thermoregulation via changing blood flow, is the
dermis
When the body is overheated, the skin responds by
dilating blood vessels
Which of the following is the correct order of the layers of the cutaneous membrane from outside to inside?
epidermis, dermis, hypodermis
Through which mechanism does perspiration function in cooling the body?
evaporation
During skin repair, most of the scab consists of an insoluble network of ________, a protein that forms from blood proteins during the clotting response.
fibrin
During the regeneration process of the skin after an injury, what is the combination of blood clot, fibroblasts, and an extensive capillary network called?
granulation tissue
Hair is formed by the repeated divisions of epithelial stem cells in which structure?
hair matrix
Through which cellular interactions are the cells of the stratum basale firmly attached to the plasma membrane?
hemidesmosomes
The loose connective tissue that separates the integument from deeper tissues and organs is called the
hypodermis or subcutaneous layer
A thickened area of scar tissue that is covered by a shiny, smooth epidermal surface is called a(n)
keloid
The protein that contributes to many of the skin's protective qualities is called ________.
keratin
The pale crescent area of the nail is called the
lunula
Modified and specialized sweat glands that produce milk are called ________ glands.
mammary
In albinism, ________ is lacking.
melanin
The most severe type of skin cancer is most likely to develop from
melanocytes
Thick skin can be found on the
palms
Which of the following is the function of hair associated with a nerve fiber?*
provides an early-warning system that may help prevent injury
Functions of the skin include
regulating body temperature
The ________ layer of the skin contains bundles of collagen fibers and elastin, and is responsible for the mechanical strength and flexibility of the skin.
reticular
The epidermal layer whose cells have stopped dividing and started to produce large amounts of keratin is the*
stratum granulosum
Epidermal cells synthesize this vitamin when exposed to sunlight.*
vitamin D3
The skin may turn orange as a result of ________ buildup.
carotene
Perspiration that is produced by apocrine sweat glands
is limited to the hair follicles of the axilla, nipples, and groin.
What is the function of melanin?
it protects DNA from the damaging effects of ultraviolet radiation
The type of burn that injures the hypodermis, deeper tissues, and organs is a(n)
3rd degree burn
Glands that are located in the passageway of the external ear are called ________ glands.
ceruminous