Ch. 6 Integumentary System

Eccrine sweat glands

respond primarily to elevated body temperature.

What determines the color of skin?

The amount of melanin that melanocytes produce.

Corns are

keratinized conical masses on toes.

Skin wrinkles with age because

fat is lost from the subcutaneous layer and the dermis shrinks.

Hypothermia is

a lowered body temperature.

The arrector pili muscle is attached to

a hair follicle.

The dermis is composed largely of

dense irregular connective tissue.

An autograft covers an injured area of skin with

skin from an uninjured region of the patient’s body.

As a person ages, the skin typically becomes

a different color.

Which of the following happens first after a scab forms?

fibroblasts from the wound edge form new collagenous fibers.

Inflammation makes skin

red, swollen and painful to touch.

The skin appears yellowish if a person eats too much

carotene.

The subcutaneous layer is

not part of the skin

Exposure to ultraviolet radiation greatly increases the risk of developing

skin cancer.

A nail consists of a

nail bed and nail plate.

The epidermis

all of the above.

The flexible proteins that link the cell membranes of squamous epithelial cells in skin are

cadherins

A person exercising vigorously on a hot, humid day may develop

all of the above

In a condition called incontinentia pigmenti, the skin has deep dark splotches, due to melanin that seeps down into the dermis. Normally, melanin is confined to the

epidermis.

Inflammation is

a normal response to stress or injury.

Which is the most likely explanation for the defect in dystrophic epidermolysis bullosa, in which the skin blisters with any touch?

collagen fibrils that attach the epidermis to the dermis break down.

Individuals at elevated risk for hypothermia include

all of the above

The subcutaneous layer of skin consists of

areolar and adipose tissue.

Epidermis is ________________, whereas dermis is ________________.

composed of stratified squamous epithelial tissue; composed of connective tissue, smooth muscle, and nerve cell processes

We enjoy sunbathing because it stimulates keratinocytes to release

beta endorphin.

Exposure to ultraviolet light darkens skin by stimulating synthesis of

melanin

Sweat cools the body by

evaporation.

A man who has a heart valve from a pig has a(n)

xenograft.

The major blood vessels that supply the skin are in the

subcutaneous layer.

A burn affecting only the epidermis is a

superficial partial-thickness burn.

Acne is a disorder of the

sebaceous glands.

Blood vessels in the ___________ supply epidermal cells with nutrients.

dermis

The advantage of cryo-electron tomography is that it

preserves intercellular junctions.

Accessory structures of the skin originate from the

epidermis.

After a severe burn, new skin may grow outwards from the hair follicles. New growth begins here because

a hair follicle contains stem cells in the bulge region.

Shafts of hair are composed of

dead epidermal cells.

Fever is

a special case of hyperthermia in which body temperature rises in response to an elevated set point, typically in response to infection.

Elderly persons may become less able to maintain stable body temperatures because

the number of sweat glands diminishes.

The nail plate is produced by

specialized epithelial cells.

As cells are pushed from the deeper portion of the epidermis toward the surface,

they die.

Gray hair is

a mixture of pigmented and unpigmented hairs.

Skin cancer is most likely to develop from

nonpigmented epithelial cells.

You step out of the shower and vigorously rub your skin with a towel. If you were able to analyze the towel, you would find skin cells. They are most likely

keratinized epidermal cells.

Nerve fibers scattered throughout the dermis are associated with

muscles, glands, and sensory receptors.

Eccrine sweat glands differ from sebaceous glands

all of the above.

Reddened skin reflects

dilated blood vessels sending more blood to the dermis.

Skin cells play an important role in producing

vitamin D.

Apocrine sweat glands are most abundant on or in the

axilla.

The hardness of a nail comes from

keratin.

Milk and ear wax

are secreted from modified sweat glands.

Examining skin under a light microscope is difficult because the preparation

removes important proteins from the cells.

The melanocytes in very dark skin

contain single, large, pigment granules.

The skin dissipates excess body heat by

all of the above

The layer of the epidermis that includes melanocytes and a single row of columnar cells that undergo mitosis is the

stratum basale.

Pigment recipient cells

are a type of keratinocyte.

A warm surface loses heat to the air molecules continuously circulating over it by

convection

The epidermis is about ___ mm thick and the dermis is about ___ mm thick.

.07 to 12; 1 to 2

Which of the following is a normal response to excessive loss of body heat in a cold environment?

Dermal blood vessels constrict.

The nerve fibers in the dermis stimulate

muscles and glands in the dermis.

The functions of skin include

regulating body temperature.

The human integumentary system includes

skin, nails, hair follicles, and glands.

In treating a burn patient, the "rule of nines" is used to estimate the

surface area of the burn.

Which person is at highest risk of developing a cutaneous carcinoma?

a light-complexioned man age 52 who goes to the beach on summer weekends and does not use sunblock because he likes to be tan.

A future treatment for baldness may potentially be

stem cells from the bulge region at the base of hair follicles.

Sebaceous glands secrete

fat globules that mix with cellular debris, forming sebum.

A hair is distinguished from a hair follicle by

being dead.

Which of the following is not correct concerning the skin?

The subcutaneous layer is between the dermis and the epidermis.

In the inherited disease ichythyosis, the skin is rough, brown, and very scaly because the uppermost layer cannot peel off as easily as it normally does. The part of the skin that is affected is the

epidermis.

An organ consists of

two or more tissues grouped together that function together.

In areas of the skin where the epidermis is thin, the ________ may be absent.

stratum lucidum

Two thieves steal jewelry, and then drop it as they are escaping. The police recover the jewelry, and an officer explains on the evening news that the back of a watch had beautiful fingerprints. The thieves, whose prints are not on file, believe that they can escape prosecution by using acid to remove the epidermis on their fingerpads, erasing their fingerprints. They are wrong because

the prints arise from the dermis, which is not destroyed.

A woman undergoes coronary bypass surgery, in which a blood vessel from her leg is moved to her heart, where it supplements the blood supply following a heart attack. This procedure is a(n)

autograft.

Body heat is lost primarily by

radiation

Eumelanin and pheomelanin are

brownish-black and reddish-yellow pigments, respectively.

A man donates part of his liver to his daughter, who suffers from cystic fibrosis. This procedure is a(n)

allograft

Cutaneous melanomas are associated with

short exposure to high-intensity sunlight.