A&P Exam 1 Ch. 5

When a person becomes "pale," what is the physiologic basis?

The blood supply to the skin decreases

What is the function of melanin?

It protects DNA from the damaging effects of ultraviolet radiation.

This layer is composed of a high concentration of collagen fibers.

dermis

A small amount of ultraviolet radiation is beneficial because it

stimulates vitamin D3 synthesis in the epidermis

The layer of the epidermis at the exposed surface is the

stratum corneum

Mammary glands are modified

sweat glands

When the arrector pili muscles contract,

"goose bumps" are formed

Why are injections administered in the hypodermis when administering drugs using a hypodermic needle?

Since it is vascularized, the hypodermis can absorb a lot of fluid.

The condition that results from clogged sebaceous glands is

acne

In other mammals, the ________ glands function as scent glands, providing an important form of communication.

apocrine

The glands that begin discharging a sticky, cloudy, and potentially odorous secretion at puberty are called ________ glands.

apocrine

The subcutaneous layer consists of

areolar and adipose tissues

What is the composition of the papillary layer of the dermis?

areolar connective tissue

The ________ is associated with the puckering of skin and the pulling of the hair follicle.

arrector pili

Which of the following conditions is the most common form of skin cancer?

basal cell carcinoma

The nail ________ covers the nail bed.

body

Exposure of the skin to ultraviolet light

can increase melanocyte activity

Glands that are located in the passageway of the external ear are called ________ glands.

ceruminous

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 skin is also called the ________ membrane

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

The dermis is composed largely of

dense irregular connective tissue

Projections of loose connective tissue from the dermis, which extend upward between the adjacent ridges of the epidermis, are called

dermal papillae.

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

Which of the following is the correct order of the layers of the cutaneous membrane?

dermis, dermis, hypodermis

When the body is overheated, the skin responds by

dilating blood vessels

The most mitotically active part of the skin is structure

epidermis

The walls of each hair follicle contain all the cell layers found in which of the following?

epidermis

Thin skin is defined by the thickness of the

epidermis

Through which mechanism does perspiration function in cooling the body?

evaporation

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 lipid in oil glands is released through which type of secretion?

holocrine

Lipid is concentrated with the cells of the

hypodermis

Perspiration that is produced by apocrine sweat glands

is limited to the hair follicles of the axilla, nipples, and groin.

A hair shaft is composed of

keratin

The protein that contributes to many of the skin's protective qualities is called

keratin

The function of the secretion of a sebaceous gland is

lubrication

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 observed differences in skin color reflect the levels of ________ production

melanin

The most severe type of skin cancer is most likely to develop from

melanocytes.

Nerve fibers in the dermis most likely function in

monitoring sensory receptors in the dermis.

You have been severely burned on the right arm in a house fire, but you are now recovering. The second- and third-degree burns have destroyed the epidermis and dermis of your arm. Predict the long-term consequences of this burn.

no growth of hair in the damaged skin area

Drugs suspended in ________ or ________ can be carried across the plasma membranes of the epidermal cells.

oils; lipid-soluble solvents

The reticular layer's collagen fibers directly provide which function?

prevent damage to the tissue

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

Merocrine sweat glands

respond primarily to elevated body temperature.

The ________ layer of the dermis contains bundles of collagen fibers and elastin, and is responsible for the mechanical strength and flexibility of the skin.

reticular

Elderly people tend to have rougher skin and more brittle hair than younger people. What structure is associated with this problem?

sebaceous glands

The epidermal layer whose cells have stopped dividing and started to produce large amounts of keratin is the

stratum granulosum

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

they die

Melanin serves to protect cells in the deeper layers of the epidermis from

ultraviolet radiation.

Epidermal cells synthesize this vitamin when exposed to sunlight

vitamin D3

Which statement is true for merocrine sweat glands?

They are more numerous than apocrine sweat glands

The loose connective tissue that separates the integument from deeper tissues and organs is called the

hypodermis

Which of the following is the function of the combination of epidermal ridges and dermal papillae?

increase surface area for diffusion between the dermis and epidermis

The hypodermis

is quite elastic

Thick skin can be found on the

palms

Choose the correct order of the cell layers, or strata, in a section of thick skin, from the basement membrane toward the free surface (deep to superficial). 1. stratum lucidum 2. stratum basale 3. stratum corneum 4. stratum granulosum 5. stratum spinosum

2, 5, 4, 1, 3

The function of the arrector pili is

contraction

The skin may turn orange as a result of ________ buildup

carotene

________ is a pigment found in vegetables that can make skin appear orange or yellow.

carotene

The deepest layer of cells in the epidermis is the cells of the

stratum basale