Biology 227 study set 1

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

0.075; 0.150

The epidermis of thick skin ranges between ______ millimeters thick.

0.4 and 0.6

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

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

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

basal; mesenchyme

Hemangiomas are ______ tumors.

benign

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

blood clot

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

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

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

The epidermal ridges interdigitate with the ______.

dermal papillae

In the second step of wound healing, a blood clot temporarily patches the ______ of the wound together and acts as a barrier to prevent the entry of ______ into the body.

edges; pathogens

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

The most superficial layer of the integument is the ______.

epidermis

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

exocrine

Friction ridges on the tips of fingers are known as ______.

fingerprints

A mild sunburn with no blistering is an example of a ______-degree burn.

first

Blood is released into the wound during the ______ step of a skin wound healing.

first

Thermoregulation is a major function of ______ sweat glands.

merocrine

The most numerous and widely distributed sweat glands in the body are ______.

merocrine sweat glands

The two types of sweat glands in the skin are ______ sweat glands and ______ sweat glands.

merocrine; apocrine

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

papillary

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

pilus

To reduce the likelihood of skin cancer, people should use sunscreen regularly and avoid ______.

prolonged exposure to the sun

The secretion produced by apocrine sweat glands is viscous, cloudy, and composed of ______ and ______ that are acted upon by bacteria, producing a distinct, noticeable odor.

proteins; lipids

The apocrine sweat glands become active and produce secretory products during ______.

puberty

In what two ways are damaged skin tissues normally repaired?

regeneration; finrosis

The deepest layer of the dermis is the ______ layer.

reticular

The secretions from sebaceous glands, called ______, are usually deposited into a ______.

sebum; hair follicle

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

selectively

Apocrine sweat glands are classified as ______ glands

simple, coiled, and tubular

Merocrine sweat glands are classified as ______ glands that release their secretion onto the surface of the skin.

simple, coiled, and tubular

Sunscreen usage reduces the likelihood of ______.

skin cancer

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

spinosum and granusoum

As an individual ages, the skin repair processes take longer to complete because of the reduced number and activity of ______ cells.

stem

In aging skin, the reduced ______ cell activity in the epidermis results in ______ skin that is less likely to protect against mechanical trauma.

stem; thinner

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

The secretion from merocrine sweat glands is carried to the surface of the epidermis via ______. The secretions of apocrine sweat glands are carried into ______.

sweat ducts; hair follicles

The major function of merocrine sweat glands is ______.

thermoregulation

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

transpiration

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

true

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

true

At puberty, terminal hair replaces ______ hair in the armpits and pubic regions of the body.

vellus

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

vellus

vernix caseosa

waterproof protective covering composed of sebum and sloughed off cells

______ glands are also called sweat glands.

Sudoriferous

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

sebum

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

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

texture; pigmentation

True or false: Regeneration in the skin replaces damaged or dead cells with the same cell type and restores organ function.

true

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

true

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

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

epidermis; redness

Apocrine and merocrine sweat glands release their secretory products by the process of ______.

exocytosis

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

false

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

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

thin

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

transdermal

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

dead

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

granulosum

Terminal hair is the type of hair that grows on the ____ , and is also the hair of _______ and eyebrows, the axilla, and the pubic region. In men, it also grows on the face.

head ; eyelashes

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

salts; urea

Sebaceous glands are activated primarily by ______ during puberty in both sexes.

sex hormones

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

sweat; sebaceous

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

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

nucleus

Hair is found almost everywhere on the body except the sides and ______ of the hands and fingers, the sides and __________ of the feet and toes, the lips, and portions of the external genitalia.

palms ; soles

______ acts as a lubricant to keep the skin and hair from becoming dry, brittle, and cracked.

sebum

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.

strata ; thickness

The skin is best described as ______.

water resistant

As an individual ages, skin repair processes take ______.

longer

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

lucidum

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

Skin repair and regeneration usually takes about ______ weeks in a healthy young person but can often take ______ that time for a person in his or her 70s.

3; twice

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

4

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

Sebaceous glands are classified as ______ glands that discharge an oily, waxy secretion called ______.

holocrine; sebum

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

hypodermis

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

keratin

Within the stratum, granulosum begins a process called ______.

keratinization

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

kidney ; skin ; liver

During our lives, we produce three kinds of hair: ___, ___, and ___ hair.

lanugo; vellus; termminal

periderm

layer of cells covering the developing embryonic epithelium

mesenchyme

layer of embryonic cells that develops into the dermis

Motile cells in the dermis are called ______ cells.

dendritic

True or false: The palms of the hands have more hair than the soles of the feet.

false