human anatomy chapter 5

Describe the lunula.

it is the half-moon shaped region at the proximal end of the nail bed.

Which layer of the epidermis contains dark staining clusters of keratohyalin?

stratum granulosum

The dermis lies deep to the epidermis and is composed of _____.

connective tissue

The reticular layer of the dermis may best be described as ______.

dense irregular connective tissue

Which structure nourishes the hair cells?

dermal papilla

Friction ridges are the external expression of the ______.

dermal papillae

In some areas of the body the boundary between the dermis and epidermis is irregular. The wavy upward projections of the dermis are called ______.

dermal papillae

Cells in the stratum spinosum are nourished by blood vessels located in the ______.

dermis

Freckle color, size and number are influenced by ______.

exposure to sunlight and heredity

The distal portion of the nail plate becomes the _________ edge.

free

The distal portion of the nail plate becomes the ________.

free edge

Fingerprints are caused by which of the following?

friction ridges

Hair and nails are composed of hard keratin while the stratum corneum is mostly soft keratin. The difference is _______.

hard keratin is compact and crosslinked

Which of the following tissue types are found in the dermal layer of the skin?

-connective tissue -muscular tissue -nervous tissue -epithelial tissue

Functions of the skin include which of the following?

-resistance to trauma and infection -water retention -vitamin d synthesis -sensation -thermoregulation -nonverbal communication -sensory reception -protection of ultraviolet light

List the layers of the epidermis in order of deepest to most superficial.

-stratum basale -stratum spinosum -stratum granulosum -stratum lucidum -stratum corneum

List the layers of the epidermis in order of most superficial to deepest.

-stratum corneum -stratum lucidum -stratum granulosum -stratum spinosum -stratum basale

The subcutaneous layer is ______.

a layer of areolar and adipose tissue below the dermis

Which of the following describes the dermal papilla that is associated with hair?

an extension of the vascular system into the hair bulb

Cutaneous glands found in the groin, axilla, areolar, and beard area are classified as ____________ sweat glands

apocrine

Identify the type of glands that are found in the groin and areola regions.

apocrine

The epidermis, like all epithelial tissue, lacks ______.

blood vessels

What are the three zones of a hair?

bulb, shaft, root

The eponychium is commonly called the ______.

cuticle

What are the three concentric regions of the hair from the outside to the inside?

cuticle, cortex, medulla

stratum spinosum and stratum granulosum=

dendritic cells

Which of the following best describes hair?

dead, keratinized cells

Hair and nails are composed of ______.

dead, keratinized epidermal cells

Cells of the epidermis that stand guard against pathogens that breach the surface of the skin are ______.

dendritic cells

defend against microbes

dendritic cells

in which location would you EXPECT to find flexion lines?

digits, palms, wrists, elbows, knee, and other places

The acid mantle of the skin helps to ______.

discourage the growth of bacteria and fungi

Describe a mole.

elevated patch of melanized skin

Downward extensions of the epidermis at the dermis and epidermal boundary are called ______.

epidermal ridges

The epithelial root sheath of the hair follicle originates in the ______.

epidermis

The hyponychium is the ______.

epidermis of the nail bed

Which of the following sequences correctly describes the layers of the integument from the most superficial to the deepest layers?

epidermis, dermis, subcutaneous

what are the two layers of the hair follicle?

epithelial root sheath and connective tissue root sheath

The area of dead skin that overhangs the lunula is called the ______.

eponychium

True or false: During a manicure, it is the nail matrix that is trimmed.

false

True or false: Freckles are patches of keratinocytes that result from exposure to sunlight.

false

True or false: Melanocytes are the only darkly pigmented cells in the epidermis.

false

True or false: The epidermis is composed of keratinized simple squamous epithelium.

false

True or false: The follicle is a zone of a hair.

false

The epidermis of the nail bed is called the ______.

hyponychium

Flexion lines occur ______.

in the skin where it folds around flexing joints

The hair and nails are composed primarily of ______.

keratin

The epidermis is composed of ______.

keratinized stratified squamous epithelium

Keratin, a protein associated with the skin, is produced by ______.

keratinocytes

One type of epidermal cell produces a protein that increases the durability of the skin. What cells are these?

keratinocytes

all layers of the epidermis=

keratinocytes

produces the tough structural protein of the epidermis

keratinocytes

Thick skin contains a clear layer packed with eleidin called the stratum ____.

lucidum

The crescent-shaped region at the proximal end of the nail bed consists is called the ______.

lunula

A hair is formed by mitotic cells in which region?

matrix

At the center of each hair is a loosely arranged core of cells and air spaces. This region is called the ______.

medulla

deposit pigment in the interstitial spaces in the epidermis

melanocytes

produces the pigment that shields the DNA from ultraviolet radiation

melanocytes

stratum basale=

melanocytes and stem cells

A elevated patch of melanized skin is a(n) _____________

mole

Which term refers to the portion of a fingernail or toenail that is attached to the tip of the digit (finger)?

nail body

The skin surrounding the nail is called the ______.

nail fold

The part of the nail which extends proximally under the skin is called the _____.

nail root

Sebaceous glands produce secretion that is characterized as which of the following?

oily

What are the two zones of the dermis?

papillary and reticular layer

The dermis consists of two zones: the more superficial _________ layer and the deeper ____________ layer.

papillary; reticular

Which of these layers is the deepest layer of the dermis and composed of dense irregular connective tissue?

reticular layer

The part of the nail which extends proximally under the skin is called the nail ____________

root

Name the oily component of the secretion of the sebaceous glands.

sebum

Which portion of the hair is found above the epidermis?

shaft

You visit your local hairdresser for a hair cut. What anatomic structure is being cut?

shaft

What are piloerector muscles?

smooth muscle fibers attached to the connective tissue root sheath

Which layer of the epidermis is seen only in thick skin?

stratum lucidum

touch receptors

tactile disc

What happens when piloerector muscles contract?

the hair "stands on end"

Which portion of the hair lies between the bulb and the shaft?

the hair root

The hair root is ______.

the portion of the hair above the bulb, but still in the skin

What is the hair matrix?

the region of actively mitotic cells above the papilla

Dermal papillae are ______.

the upward projections of the dermis at the dermis-epidermis boundary

The stratum granulosum can best be described as:

three to five layers of keratinocytes filled with clusters of keratohyalin

in which location would you NOT EXPECT to find flexion lines?

umbilicus