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