Integumentary System and Body Temperature Flashcards
Which system does the skin, its accessory structures (sweat glands, oil glands, hair, and nails), and the subcutaneous tissue below the skin form?
Integumentary
Which system acts as a mechanical barrier by keeping harmful substances out of the body and helping to retain water?
Integumentary
Which system acts as a chemical barrier of the skins surface by protecting it with the acid pH?
Integumentary
Which system protects the internal structures and organs from injuries caused by blows, cuts, harsh chemicals, sunlight, burns, and pathogenic microorganisms?
Integumentary
Which system participates in the immune response against invading microbes by housing specialized cells, called dendritic or Langerhans cells?
Integumentary
Which system performs an excretory function?
Integumentary
Although excretion is a minor role, the skin is able to excrete water, salt, and small amounts of waste, such as urea.
Which system acts as a gland by synthesizing vitamin D when exposed to sunlight?
Integumentary
Vitamin D is necessary for the absorption of calcium from the digestive tract.
Which system performs a sensory role by housing the sensory receptors for touch, pressure, pain, and temperature?
Integumentary
In this way, the skin helps to detect information about the environment.
Which system plays an important role in the regulation of body temperature?
Integumentary
Integumentary Membrane
Cutaneous Membrane
Which organ is the largest in the body?
Cutaneous (Skin)
Which two distinct layers make up the skin?
Epidermis
Dermis
Which skin layer is the outer or surface?
Epidermis
Which skin layer is the inner?
Dermis
Which skin layer is anchored to a subcutaneous layer?
Dermis
What is the study of the skin and its disorders?
Dermatology
Which thin outer layer of skin is composed of stratified squamous epithelium?
Epidermis
Like all epithelial tissue, the epidermis is ___; it has no blood supply of its own.
avascular
Oxygen and nutrients diffuse into the lower epidermis from the rich supply of blood in the underlying ___.
dermis
The epidermis can be divided into five layers. Two of the layers are the deeper stratum ___ and the more superficial stratum ___.
germinativum
corneum
Which epidermal layer lies on top of the dermis and thus has access to a rich supply of blood?
Stratum Germinativum
Which epidermal layer has cells that are continuously dividing, producing millions per day?
Stratum Germinativum
The cells undergo a process of ___ization, whereby a tough protein, ___, is deposited within the cell. The ___ hardens and flattens the cells as they move toward the surface of the skin.
keratin x 3
As the cells divide, they push the older cells up toward the surface of the epithelium. As the cells move away from the dermis (their source of nourishment) the cells begin to die.
Which protein makes the skin water resistant in addition to hardening the cells?
Keratin
Which epidermal layer is the surface layer and is composed of about 30 layers of dead flattened keratinized cells?
Stratum Corneum
What are the dead, flattened, and keritanized cells that are continuously sloughed off, exfoliated, or desquamated through wear and tear?
Dander
The sloughed cells are replaced by other cells that are constantly moving up from the deeper layers. You shed about 40,000 skin cells each minute; each month you have a new layer of epithelium. Interesting fact: the ink used in creating a tattoo must be deposited into the dermis because of the sloughing characteristic of the epidermis.
What is dander clumped together by the skull’s oil?
Dandruff
Which portion of the skin is the largest and located beneath the epidermis?
Dermis
Which skin portion is composed of dense fibrous connective tissue?
Dermis
Which skin portion contains numerous collagen and elastin fibers surrounded by a gel-like substance?
Dermis
The fibers make the dermis strong and stretchable; note how well the skin stretches during pregnancy and weight gain. Sometimes, however, excessive stretching of the skin causes small tears in it, seen as white lines. These lines are called stretch marks, or striae.
Where are accessory structures such as hair and certain glands embedded within?
Dermis
Where are blood vessels, nervous tissue, and some muscle tissue located within?
Dermis
Where are the nerves that have specialized endings called sensory receptors that detect pain, temperature, pressure, and touch found?
Dermis
What tells stories of systemic disease, drug reactions, exposure to irritants, and emotional distress?
Skin
Which disease type may be characterized by lesions or changes in the skin?
Systemic
Which disease type does a person with herpes zoster (shingles) - an inflammation of nerves caused by the chickenpox virus - when painful skin lesions develop along the path of the nerve?
Systemic
Which disease type is evident when a person with a severe generalized staphylococcal infection develops scalded skin syndrome, a condition in which the skin appears scalded and peels off in layers?
Systemic
___ reactions are often revealed by skin changes. For example, a person allergic to penicillin may develop hives or urticaria.
Similarly, a person allergic to sulfa ___ may develop a generalized rash that can progress to a lethal condition called Stevens-Johnson syndrome.
Drug
drugs
Chronic irritation causes skin changes.
For example, constant irritation or rubbing of an area causes the rate of epidermal cell division to increase, producing a thickened area called a ___.
Constant rubbing of a toe by a poorly fitting shoe can also produce an overgrowth of epidermal cells arranged in a conical shape. This overgrowth is called a ___.
callus
corn
The skin mirrors your ___ temperature. For instance, when stressed, humans sometimes break out.
emotional
Which layer does the dermis lie on?
Subcutaneous
Which layer is not considered part of the skin because it lies under the skin?
Subcutaneous
Subcutaneous Layer
Hypodermis
Which layer is composed primarily of loose connective and adipose tissue?
Subcutaneous
Which layer’s role is to help insulate the body from extreme temperature changes in the external environment and anchor the skin to the underlying structures?
Subcutaneous
Which layer do few areas of the body lack?
Subcutaneous
What layer does skin lack when it anchors directly to the bone?
Subcutaneous
Which layer does the skin over knuckles lack?
Subcutaneous
It is wrinkled and creased because it attaches directly to bone.
Which absorption method includes drugs being placed on the surface of the skin to achieve a systemic effect (throughout the body)?
Transdermal
Across the Skin
Which route includes nitroglycerin being applied using an adhesive patch on the skin?
Transdermal
Which route includes a drug penetrating the skin and being absorbed by the dermal blood vessels where it is transported by the blood throughout the body and exerts its effects?
Transdermal
Which absorption route is used to detect allergies by injecting antigens (possible allergic substances)?
Intradermal
Which absorption route is used when drugs are applied on the surface of the skin and exerts its effect locally?
Topical
Which absorption route is a common way to inject drugs for faster systemic effects?
Subcutaneous
The Skin
What are deep within the epidermal layer and secrete a skin-darkening pigment?
Melanocytes
Which pigment stains the surrounding cells, causing them to darken?
Melanin
The more melanin secreted, the darker the skin color. Interestingly, we all have the same numbers of melanocytes. What determines our skin color is not the numbers of melanocytes but the amount of melanin secreted.
Which cells increase their secretion of melanin when exposed to the ultraviolet radiation of sunlight?
Melanocytes
The skin darkens in an attempt to protect the deeper layers from the harmful effects of radiation. This effort creates the famous summer tan.
What is skin’s three accessory structures?
Hair
Nails
Glands
Which skin accessory structure’s function is to sense insects on the skin before they can sting us?
Hair
Which skin accessory structure’s function is to protect the eyes from dust and perspiration; trap dust and prevent it from being inhaled into the lungs; and keep up warm?
Hair
By which two hormones are hair growth and distrbution influcenced?
Estrogen
Testosterone
By which hormone is the growth of hair in the axillary and pubic areas in males and females caused?
Testosterone
In the man, testosterone produces a beard and hairy chest. When a woman has too much testosterone, excessive hair growth occurs, including facial hair. The excessive growth of hair is called hirsutism, from a Greek word meaning “shaggy.”
What are the two chief hair parts?
Shaft
Root
Which hair part is above the surface of the skin?
Shaft
Which hair part extends from the dermis to the surface?
Root
Each hair arises from a group of epidermal cells that penetrate the ___.
This downward extension of epidermal cells forms the hair ___.
The epidermal cells of the hair ___ receive a rich supply of blood from the ___ blood vessels.
dermis
follicle x 2
dermal
As the hair epidermal cells divide and grow, the older cells are pushed toward the surface of the skin.
As they move away from their source of nourishment, the cells die.
Like other cells that compose the skin, the hair cells also become ___.
The hair that we brush, blow dry, and curl every day is a collection of dead, ___ cells.
keratinized x 2
By which secretion is hair colour determined depending on its amount?
Melanin
An abundance of melanin produces dark hair, whereas less melanin produces blond hair. With age, the melanocytes become less active; the absence of melanin produces white hair. Gray hair is caused by a mixture of pigmented and nonpigmented hairs. Interestingly, red hair is caused by a modified type of melanin that contains iron.
Which hair part’s shape determines if hair is curly, wavy, or straight?
Shaft
A round shaft produces straight hair, whereas an oval shaft produces wavy hair. Curly and kinky strands of hair are the result of flat hair shafts. Hair can be curled by chemically flattening the hair shafts.
What are the group of smooth muscle cells attached to the hair follicle?
Arrector Pili
What muscle contractions cause the hair to stand on end?
Arrector Pili
Which muscle contraction causes hair to stand on end?
Arrector Pili
Hair Follicle and Parts of the Hair
What are thin plates of stratified squamous cells that contain a very hard form of keratin?
Nails
What are found on the distal ends of the fingers and toes and protect these structures from injury?
Nails
What is the nail’s three structures?
Free Edge
Body (Fingernail)
Root
The condition of the nails provides important diagnostic information regarding systemic disease.
Nails should be examined for shape, dorsal curvature, adhesion to the nail bed, color, and thickness.
Where do the cells that the nail body develop keratinize?
Root
What half-moon-shaped structure represents the extent of nail growth and is located at the base of the nail?
Lunula
Which epidermal layer does the lunula slide over as the nail body grows?
Nail Bed
What is beneath the dermal layer that causes the pink nail colour?
Blood Vessels
What is the fold of stratum corneum that grows onto the proximal portion of the nail body?
Cuticle
Nail
Which two major exocrine glands are associated with the skin?
Sebaceous
Sweat
Which exocrine glands are associated with hair follicles and are found in all areas of the body that have hair?
Sebaceous (Oil Glands)
Which exocrine glands secrete an oily substance called sebum that flows into the hair root and then out onto the surface of the skin?
Sebaceous (Oil Glands)
A small number of sebaceous glands open directly onto the surface of the skin.
What lubricates and helps waterproof the hair and skin; it also inhibits the growth of bacteria on the surface of the skin?
Sebum
With aging, sebum production gradually decreases. This change partly accounts for the dry skin and brittle hair seen in older persons.
Which two exocrine gland types are located in the dermis?
Sudoriferous (Sweat Glands)
Sebaceous (Oil Gland)
Which two exocrine glands secrete sweat?
Apocrine
Eccrine
The sweat is secreted into a duct that opens onto the skin as a pore.
Which sweat glands are usually associated with hair follicles and found in the axillary and genital areas?
Apocrine
Which sweat glands respond to emotional stress and become active when the person is frightened, upset, in pain, or sexually excited?
Apocrine
Which sweat glands become more active during puberty because their development is stimulated by the sex hormones?
Apocrine
The sweat produced by these glands does not have a strong odor.
If allowed to accumulate on the skin, however, the substances in sweat are degraded by bacteria into chemicals with a strong unpleasant odor.
This is called body odor and is the reason we use deodorant.
Some of these secretions act as sex attractants.
Watch how eagerly Rover sniffs when a potential mate is in the immediate area.
These sex attractants are called pheromones.
The vaginal secretions of an ovulating female contain pheromones called copulines.
The copulines can cause a testosterone surge (and an urge to merge) in the male.
Which are the more numerous and widely distributed of the sweat glands?
Eccrine
Which sweat glands are located throughout the body and are especially numerous on the forehead, neck, back, upper lip, palms, and soles?
Eccrine
Which glands are not associated with hair follicles?
Eccrine
Skin Glands
What is measured by a thermometer?
Body Temperature
Normal body temperature is said to be 98.6°F, although it can range from 97° to 100°F. The temperature fluctuates about 1.8°F in a 24-hour period, being lowest in the early morning and highest in the late afternoon. Body temperature also differs from one part of the body to another. The inner parts of the body (cranial, thoracic, and abdominal cavities) reflect the higher core temperature. The more surface areas (skin and mouth) reflect the cooler shell temperature. For example, the rectal temperature measures core temperature and ranges between 99° and 99.7°F, whereas the oral and axillary temperatures are about 1°F lower.
Body temperature is maintained by balancing heat production and heat loss.
What is the regulation of body temperature?
Thermoregulation
Failure to ___ causes body temperature to fluctuate outside the normal range.
thermoregulate
Extreme changes in body temperature can be fatal.
What is an excessive decrease in body temperature?
Hypothermia
What is an excessive increase of body temperature?
Hyperthermia
What is thermal energy and is produced by the millions of chemical reactions occurring in the cells of the body?
Heat
The heat is picked up and distributed throughout the body by the blood. In the resting state, the greatest amount of heat is produced by the muscles, liver, and endocrine glands.
Which thermal energy’s production amount can be affected by many factors, such as food consumption, the amounts and types of hormones secreted, and physical activity?
Heat
With exercise, the amount of heat produced by the muscles may increase enormously. The hormonal effects on heat production are dramatically illustrated by persons with thyroid gland disease. The hypothyroid person generally has a lower-than-normal body temperature and complains of being cold. The hyperthyroid person has an elevated temperature and complains of being hot. In fact, an extreme hyperthyroid state (thyroid storm) can elevate body temperature into a range that is potentially lethal.
Where does 80% of heat loss occur?
Skin
Heat loss is achieved through changing the amount of blood delivered to the skin and also through the secretion of sweat.
20% of heat is lost through the ___ system (___) and in the ___ products (urine and feces).
respiratory, lungs
excretory
Where is the thermostat of the body?
Hypothalamus
What senses changes in body temperature and sends information to the skin (blood vessels and sweat glands) and skeletal muscle?
Hypothalamus
In which two ways does the body respond to temperature elevation?
Perspiration (Sweating)
Chilling (Dilating)
When the blood vessels of the skin ___, they allowing more blood to flow to the skin.
This activity transfers heat from the deeper tissues to the surface of the body.
Temperature elevation also stimulates the activity of the sweat glands.
As the sweat ___ from the surface of the body, heat is lost.
dilate
evaporates
Under extreme conditions of heat, 12 L of sweat can be secreted in a 24-hour period.
Note how flushed our jogger is because of the blood coming to the surface.
Heat radiates from the warm reddened skin blood to the surrounding environment, thereby lowering body temperature.
In which two ways is perspiration classified?
Sensible
Insensible
Which perspiration refers to the activity of the eccrine glands on a hot day; these glands secrete sweat onto the surface of the skin?
Sensible
As the sweat evaporates, heat is lost. A significant amount of water can be lost with profuse sweating, so much so that the person may become dehydrated, experience low blood volume, shock, and die.
Which perspiration refers to the secretion of a small amount of sweat; it occurs before one is aware of or senses the sweating?
Insensible
Insensible Water Loss
Which perspiration includes the water lost through evaporation from the lungs (approximately 500 mL/day)?
Insensible
When the body responds to a decreased temperature, the blood vessels in the skin ___, reducing blood flow to the skin.
Second, the sweat glands become less active, also preventing heat loss through ___.
constrict
evaporation
This response traps the blood and heat in the deeper tissues, preventing heat loss.
What causes skeletal muscles to contract vigorously and involuntarily, increasing in the production of heat?
Shivering Thermogenesis
Contraction of the ___ ___ muscles causes goose bumps, indicating a decline in body temperature, but contributing minimally to heat conservation.
arrector pili
In furry animals, the story is a little different; contraction of the arrector pili muscles pulls the fur upright, thereby trapping warm air. So, it’s not good to shave Rover in the winter.
What produces only about two-thirds of the heat produced by an adult but loses twice as much?
Infant (Neonate)
Several factors contribute to the excess heat loss.
The neonate generally has a large surface area, which increases heat loss. The curled-up position of the infant decreases surface area and conserves heat. Interestingly, considerable heat is lost from the head area; hence, the use of caps in the newborn nursery.
The neonate generally has only a thin layer of subcutaneous fat (fat acts as an insulator, thus preventing heat loss.)
Although we are generally concerned about excessive heat loss in the neonate, we must also be concerned about excess heat. An infant has a very limited capacity to dissipate heat and is therefore at risk for hyperthermia. Do not leave the baby in a hot car!
The neonate cannot shiver (shivering produces heat).
The neonate, like a squirrel, produces heat by a process called ___ ___.
A neonate has brown adipose tissue (BAT), or brown fat, scattered throughout its body, especially around the neck and shoulder area.
Metabolism of BAT generates more heat than the metabolism of ordinary adipose tissue (white fat).
The heat produced by BAT is picked up by the blood and dispersed throughout the body.
nonshivering thermogenesis
Which four terms describe heat transfer?
Every - Evaporation
Rabbit - Radiation
Carries - Conduction
Carrots - Convection
Which transfer occurs when heat is lost from a warm object (the body) to the cooler air surrounding the warm object?
Radiation
Which heat transfer transpires when a person loses heat in a cold room?
Radiation
Which transfer is the loss of heat from a warm body to a cooler object in contact with the warm body?
Conduction
Which heat transfer exists when a person (warm object) becomes cold when sitting on a block of ice (cooler object)?
Conduction
Clinically, a cooling blanket may reduce a dangerously high fever.
Which transfer is heat loss by cool air currents moving over the surface of the skin?
Convection
Which transfer occurs when a fan moves air across skin’s surface, thereby constantly removing the heated layer of air next to the body?
Convection
Which transfer occurs when a liquid turns into a gas in response to temperature?
Evaporation
During strenuous exercise, sweat on the surface of the skin ___ and cools the body.
The ___ of water is associated with the loss of a considerable amount of heat.
On a hot, humid day, water cannot ___ from the surface of the skin; thus heat loss is diminished. This is why we feel the heat so intensely on a hot, humid day.
evaporates
evaporation
evaporates
What is the normal range of body temperature from 97° to 99.6°F (36.1° to 37.6°C)?
Normothermia
Fever
Pyrexia
What is body temperature elevation caused by the body’s inability to get rid of excess heat; the body simply cannot cool itself?
Hyperthermia
The cause of hyperthermia is most often environmental; the person is subjected to prolonged exposure to high temperatures, as in the case of an infant left in a car during the hot weather.
Unlike fever, hyperthermia is not caused by resetting the thermostat; the set point is normal. Treatment measures focus on cooling the body; antipyretics are not effective because the set point is normal.
In the advanced state (104°F [40°C]), ___ is called heat stroke or sunstroke and represents thermoregulatory failure.
hyperthermia
Without immediate treatment, death ensues.
What is the decrease in body temperature that is usually caused by prolonged exposure to cold, as in falling through ice into cold water?
Hypothermia
Which term refers to the body’s temperature falling so low that the body cannot sustain its metabolism?
Hypothermia
Death usually ensues when the body temperature drops below 95°F (35°C).
Temperature Regulation
Babies are born with a covering resembling cream cheese called the vernix caseosa, which is secreted by the ___ glands.
sebaceous
Which cells alert the immune system to ward off infection when the skin is broken?
Dendritic
