Anatomy & Physiology I Chapter 6 SmartBook

Epidermal dendritic cells are found in which of the following strata? Choose all that apply.

-granulosum -spinosum

Tactile cells are described best by which of the following?

-large epithelial cells -can be stimulated by light pressure -also called Merkel cells -can be stimulated by light touch

Which organs are involved in making calcitriol, the active form of vitamin D?

-liver -kidney -skin

The main functions of the subcutaneous layer are which of the following?

-provides thermal insulation -acts as an energy reservoir -protects the body

The epidermis of thick skin ranges between ______ millimeters thick.

0.4 and 0.6

______ layers of keratinocytes comprise the stratum granulosum.

3-5

Keratinocytes of the epidermis are usually present for about ______ week(s).

4

In what important way does a freckle differ from a nevus?

A freckle is an area of excessive melanocyte activity/a nevus is caused by an increase in melanocyte numbers.

______ hemangiomas or "strawberry-colored birthmarks," appear in the skin as bright red to deep purple nodules that usually disappear in childhood.

Capillary

______ is a yellow-orange pigment acquired from vegetables like carrots, corn, and squash.

Carotene

True or false: In albinism, the individual usually has white hair, pale skin, and pink irises because they don't have melanocytes.

False

Match the letter to the appropriate integument layer.

Look at figure 6.1 A - epidermis B - papillary layer C - dermis D - reticular layer E - subcutaneous layer

Match the letter with the epidermal strata.

Look at figure 6.2 A - stratum corneum B - stratum lucidum C - stratum granulosum D - stratum spinosum E - stratum basale

Match the structures with the labels in the picture of the nail.

Look at figure 6.9 A - matrix B - root C - eponychium D - lunula E - body of nail

Match the structures with the labels on the given nail illustration.

Look at figure 6.9 A - nail plate B - nail bed C - phalanx

______ cuts to the lines of cleavage often results in slow healing and increased scarring.

Perpendicular

The ______ of the integument has immune cells.

Stratum spinosum/dermis

______ covers most of the body except for the palms of the hands and soles of the feet.

Thin

______ skin contains the following accessories: nails, hair follicles, sweat glands, and sebaceous glands.

Thin

True or false: The amount of melanin in the skin is determined by both heredity and light exposure.

True

True or false: The epidermis exhibits variations among different body regions within a single individual, as well as differences between individuals.

True

True or false: The reason the cells of the stratum spinosum have a spiny appearance when viewed under a microscope is due to shrinkage of the cytoplasm.

True

True/False All people, of all skin tones, have about the same number of melanocytes.

True

An inherited recessive condition where the enzyme needed to produce melanin is nonfunctional is called _____.

albinism

The integument is the body's largest organ and is composed of ______ basic tissue types.

all

The subcutaneous layer or hypodermis is made up of two types of connective tissue, which are ______.

areolar and adipose connective tissue

The net effect of vasoconstriction of the dermal blood vessels is a shunting of blood ______ from the periphery of the body to ______ heat.

away; conserve

Hemangiomas are ______ tumors.

benign

A hemangioma is a congenital anomaly that results in skin discoloration due to ______ that proliferate and form a benign tumor.

blood vessels

Each nail plate consists of a pinkish nail ______ and a distal whitish free ______.

body; edge

Women often accumulate subcutaneous fat in the ______, ______, hips, and thighs

breasts; buttocks

There are two types of hemangiomas, ______, and ______.

capillary; cavernous

Keratinocytes in the epidermis produce ______ when exposed to UV radiation.

cholecalciferol

Lines of cleavage (or tension lines) in the skin relate to the predominant orientation of _____ fiber bundles.

collagen

The main structural components of the reticular layer is primarily a network of ______ fibers that extend internally from the reticular layer of the dermis into the underlying subcutaneous layer.

collagen

The predominant type of protein fiber found in the dermis is ______.

collagen

The word reticular means "network" and refers to the web like meshwork of ______ fibers.

collagen

Lines of cleavage (or tension lines) in the skin identify the predominant orientation of ______ fiber bundles in the ______.

collagen; dermis

In the dermis of the skin, _____ fibers impart tensile strength while _____ fibers allow some stretch.

collagen; elastic

The specific orientation of ______ fiber bundles in the dermis is a result of the direction of applied ______ during routine movements.

collagen; stress

When the skin is stretched beyond its capacity, some ______ fibers are torn and result in stretch marks, which are called ______.

collagen; striae

The stratum ______ consists of about 20 to 30 layers of dead, scaly, interlocking keratinized cells.

corneum

There are four layers of cells in the epidermis of thin skin. From superficial to deep, these layers are stratum ______, stratum ______, stratum ______, and stratum basale.

corneum; granulosum; spinosum

Vasoconstriction means that the diameter of the vessels ______, so relatively ______ blood can travel through them.

decrease; less

The dermis is ______ to the epidermis and contains primarily ______.

deep; collagen fibers

When a person is severely burned, a primary danger is _____ because the individual has lost the protective skin barrier and water can escape from body tissues.

dehydration

In addition to keratinocytes, the stratum spinosum also contains another epidermal cell type called epidermal ______ cells that help to fight infection.

dendritic

The ______ contain(s) the capillaries that supply nutrients to the cells of the epidermis.

dermal papillae

The spiny appearance of stratum spinosum cells is primarily due to the tenacious nature of _____, which function to hold these non-dividing cells together.

desmosomes

The dermis of the skin has an extensive innervation, which refers to the ______.

distribution of nerve fibers

The keratinocytes within stratum lucidum are flattened and filled with the protein ______, an intermediate product in the process of keratin maturation.

eleidin

The nails, hair, and exocrine glands of the skin are known as ______.

epidermal appendages

Immune cells found in the epidermis are called ______ cells.

epidermal dendritic

The skin is made up of two distinct layers which are the ______.

epidermis, dermis

The two distinct layers of the integument consist of a layer of stratified squamous epithelium called the ______ and a deeper layer of areolar and dense irregular connective tissue called the ______.

epidermis; dermis

True or false: Melanin plays a role in Vitamin A production and normal vision as well as improved immunity.

false

Fingerprints are useful as a forensic tool because each individual has a unique pattern of ______.

friction ridges

______ are located on the fingers, palms, soles, and toes are formed from large folds and valleys on both the dermis and epidermis.

friction ridges

In the layer of the epidermis called the stratum _____, the process of keratinization begins.

granulosum

Normal skin color results from a combination of colors of ______, melanin, and carotene.

hemoglobin

When ______ binds oxygen, it exhibits a bright red color, giving blood vessels in the dermis a reddish tint that is most easily observed in the skin of lightly pigmented individuals.

hemoglobin

The subcutaneous layer is also known as the ______ or superficial fascia.

hypodermis

Vasodilation of the dermal blood vessels means that the diameter of the vessels ______, so relatively ______ blood can travel through them.

increases; more

The cells of the stratum corneum contain large amounts of the protein ______.

keratin

Within the stratum, granulosum begins a process called ______.

keratinization

The most numerous cells of the epidermis are _____ and the protein they produce is called _____.

keratinocytes; keratin

Skin is classified as either thick or thin based on two parameters: the number of epidermal _____ in the epidermis and the relative _____ of the epidermis, rather than the thickness of the entire integument.

layers; thickness

The first three strata of the epidermis consists of ______ keratinocytes and the most superficial strata contain ______ keratinocytes.

living; dead

In thick skin, there is an extra layer of epidermal cells. This layer is called the stratum ______.

lucidum

Scattered among the keratinocytes of the stratum basale are pigment-producing cells called ______.

melanocytes

The ultraviolet rays in sunlight are prevented from penetrating to the deeper dermis layer by specialized cells called ______.

melanocytes

When exposed to the sun, the ______ become more active and secrete a protein that gives the skin a tanned look.

melanocytes

A nevus is commonly referred to as a _____. It is a harmless, localized growth of _____ forming cells.

mole; melanocytes

During the process of keratinization, the cell's _____ and organelles disintegrate and the cells start to die.

nucleus

The main function of melanin pigment is to protect the _____ of keratinocytes from UV radiation.

nucleus

The ______ layer of the dermis contains areolar connective tissue and dermal papillae.

papillary

The most superficial layer of the dermis is the ______ layer.

papillary

The two layers of the dermis are the ______ layers.

papillary and reticular

Epidermal dendritic cells accomplish their immune function by their ______ activity, which initiates an immune response against invaders.

phagocytic

The ______ layer of the dermis consists primarily of dense irregular connective tissue with large bundles of collagen fibers.

reticular

The deepest layer of the dermis is the ______ layer.

reticular

The ______ of the dermis forms the deeper, major portion of the dermis and extends from the papillary layer to the underlying subcutaneous layer.

reticular layer

The substances that make sweat feel gritty are water ______ and ______.

salts; urea

______ lubricates the epidermis and hair and helps make the integument water resistant.

sebum

Because skin can absorb certain chemicals and block others, it is described as _____ permeable.

selectively

When compressed, tactile cells release chemicals that stimulate ______ endings in the dermis.

sensory nerve

After a stem cell divides in the stratum basale, the resulting daughter cell enters the stratum ______ and it begins to lose its ability to divide.

spinosum

Classify the tissue type of the epidermis: keratinized ______ epithelium.

stratified squamous

The layer of the skin from which most new epidermal cells are derived from is the ______.

stratum basale

The most superficial layer of the epidermis is the ______.

stratum corneum

The ______ layer is not part of the integumentary system.

subcutaneous

On many parts of the body, the components of the dermis include blood vessels, _____ glands, _____ glands, hair follicles, nail roots, sensory nerve endings, and smooth muscle tissue.

sweat; sebaceous

Scattered among the cells of the stratum basale are cells that are sensitive to touch. These sensory cells are called ______.

tactile cells

The stratum lucidum is found only in ______.

thick skin

There are three main variations in the epidermis. These variations are _____, colorations, and skin markings.

thickness

The delivery of drugs through the skin through the use of an adhesive patch is called ______ administration.

transdermal

The release of water vapor from sweat glands when we are not sweating is a process called _____.

transpiration

Migration of a keratinocyte from the stratum basale to the stratum corneum takes about _____ weeks. The dead, keratinized cells usually remain in the exposed stratum corneum layer for an additional _____ weeks. Overall, keratinocytes are present for about _____ month following their formation.

two; two; one

Drugs are often injected into the subcutaneous layer because its extensive ______ network promotes rapid absorption. Multiple choice question. collagen

vascular

If the body is too warm, the dermal blood vessels ______ so more blood can travel ______ to the surface and excess can be lost.

vasodilate; close