Anatomy Ch. 5: Integumentary System

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

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

The epidermis of thick skin ranges between ______ millimeters thick.

0.4 and 0.6

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

4

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

Nucleus or DNA

apocrine sweat gland

One of the large dermal exocrine glands located in the axilla and genital areas. It secretes sweat that, in action with bacteria, is responsible for human body odor.

State each terms funcitons: Periderm: Vernix caseosa: Mesenchyme:

Periderm: layer of cells covering the developing embryonic epithelium Vernix caseosa: waterproof protective covering composed of sebum and sloughed off cells Mesenchyme: layer of embryonic cells that develops into the dermis

______ glands are also called sweat glands.

Sudoriferous

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

Thin, superficial; composed of epithelial tissue

True or False: all people of all skin tones have about the same number of melanocytes.

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

Hemangiomas are ______ tumors.

benign

In the second step of wound healing, a ______ forms.

blood clot

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

epideramal

First-degree burns involve only the ______ and are characterized by ______, pain, and slight edema (swelling).

epidermis; redness

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

hemoglobin

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

keratin

Within the stratum, granulosum begins a process called ______.

keratinization

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

nucleus or nuclei

sebaceous gland

oil-secreting gland in the dermis that is associated with hair follicles

stratum lucidum

a layer of the epidermis found only in the thick skin of the fingers, palms, and soles

stratum granulosum

a layer of the epidermis that marks the transition between the deeper, metabolically active strata and the dead cells of the more superficial strata

stratum spinosum

a layer of the epidermis that provides strength and flexibility to the skin

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

body; edge

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

cholecalciferol

In the first step of wound healing, blood brings ______ proteins, numerous white blood cells, and antibodies to the site.

clotting

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

collagen

Nails are derived from the same type of cells that produce the stratum ______ layer of the epidermis.

corneum

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

The exposed parts of nails and hair are composed of _______ keratinocytes.

dead

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

dendritic

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

eleidin

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

Sebaceous glands and sweat glands are types of ______ glands of skin.

exocrine

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

granulosum

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 most superficial layer of the dermis is the ______ layer.

papillary

The two layers of the dermis are the ______ layers.

papillary and reticular

In anatomy, a single hair is also called a(n) ______.

pilus

The deepest layer of the dermis is the ______ layer.

reticular

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

sebum

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

skin liver kidney

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

spinosum granulosum

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 skin houses two types of general exocrine glands, which are ______ glands and ______ glands.

sweat; sebaceous

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

tactile cells

Differences in hair density are due primarily to differences in its ______ and ______.

texture; pigmentation

stratum basale (germinativum)

the deepest layer of the epidermis consisting of stem cells capable of undergoing cell division to form new cells

stratum corneum

the most superficial layer of the epidermis consisting of dead 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 or thinness

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

transdermal

In children, ______ is the primary human hair and is found on most of the body.

vellus

The skin is best described as ______.

water resistant

True or false: There are two major regions of the dermis: a superficial reticular layer and a deeper papillary layer.

False - reticular layer is deep and the papillary layer is superficial

The epidermis of thin skin ranges in thickness from ______ millimeters to ______ millimeters thick

0.075; 0.150

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.

2, 2, 1

In the development of embryonic skin, the _____ layer gives rise to the epidermis, and the _____ gives rise to the dermis.

Basal, mesenchyme

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

Blank 1: keratinocytes or keratinocyte Blank 2: 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.

Blank 1: strata or layers Blank 2: thickness or thinness