Anatomy Chapter 5. Integumentary system
the sweat glands that communicate with hair follicles in the armpits and produce an odorous secretion are called:
Apocrine glands
Deodorants are used to mask the effects of secretions from which type of skin gland?
Apocrine sweat gland
Deodorants are used to mask the odor for what glands?
Apocrine sweat gland secretions
How does stratum lucidum appear in the thick skin layer?
Appears as a glassy layer in the thick skin only *only found in thick skin
What is the composition of the papillary layer of the dermis?
Areolar connective tissue
The hypodermis consists of which tissue type?
Areolar tissue
The hypodermis consists of which type of tissue?
Areolar tissue
What is a bundle of smooth muscle cells that connects to each hair?
Arrector pili
Calluses form on the palms after manual labor because:
Cells of the stratum basale divide more rapidly, thickening the epithelium
In which type of burn are the superficial cells of the epidermis destroyed, but the dermis remain mostly unaffected?
First-degree burn
The loose connective tissue that separates the integument from deeper tissues and organs is the called the
hypodermis or subcutaneous layer
what covers the nail bed?
nail body
Thick skin can be found on the
palms and soles of feet
The most superficial layer of the dermis is the
papillary layer
Where are the capillaries that supply the epidermis located?
papillary layer of the dermis
Squamous cell carcinomas involve _______
the superficial layers of epidermal cells
What is another example that influences skin color?
Amount and distribution of melanin
What is a carcinoma?
Any cancer of epithelial tissue
What is thick skin?
-5 layers of cells -Very thick stratum corneum
What 2 groups of sweat glands occur in the skin?
-Apocrine sweat glands -Eccrine sweat glands
What is cyanosis and how does this happen?
-Bluish coloration -Occurs when blood oxygen supplies are diminished as in: asthma attack, heart attack
What color is oxygenated blood and what causes it?
-Bright red -Increases in body temp. -Results in a flushed, red skin color
Which two skin pigments are found in the epidermis?
-Carotene -Melanin
What does the reticular layer contain? What type of tissue?
-Contains: blood vessels, lymphatic vessels, nerve fibers, and sensory receptors -Dense irregular tissue
What does the papillary layer contain? What type of tissue?
-Contains: capillaries, lymphatic vessels, and sensory neurons that supply skin surface -Consists of areolar tissue
What fibers are responsible for the stretching of the skin during pregnancy?
Elastic fibers found in the reticular layer of the dermis
A small amount of UV radiation is beneficial because it stimulates vitamin D3 synthesis in the
Epidermis
Where are accessory organs (such as hair follicles and sweat glands) derived from?
Epidermis
What do burns result from?
Exposure to heat, radiation, electrical shock, or strong chemicals
True or false: A persons skin color depends on the number of melanocytes present in epidermis
FALSE
During skin repair, most the scab consists of an insoluble network of what? It is a protein that forms from blood proteins during the clotting response?
Fibrin
During step 4 of skin repair, which cells in the dermis continue to create scar tissue?
Fibroblasts
Coiled tubular glands that discharge their secretions onto the surface of the skin are called ___________.
Merocrine sweat glands
Coiled tubular glands that discharge their secretions onto the surface of the skin are called what?
Merocrine sweat glands
Why are skin injuries and infections more common when one is aging?
Most likely due to a thinning of the epidermis as stem cells become less active
What is NOT a function of the integumentary system?
Movement
Does the epidermis contain blood vessels?
NO, it is avascular
Which type of burn appears inflamed and feels tender but has no blisters?
First degree burn
A thickened area of scar tissue that is covered by a shiny, smooth epidermal surface is called a
Keloid
The fibrous protein that forms the basic structural component of hair and nails is what?
Keratin
The protein that contributes to many of the skin's protective qualities is called
Keratin
The skin may turn orange as a result of what buildup
Keratin
What substance makes nails hard?
Keratin
What are the majority of cells in the epidermis?
Keratinocytes: contain the protein keratin
What organs convert a precursor molecule into calcitriol, a hormone that is essential for calcium and phosphate absorption?
Kidneys
When the arrector pili muscle is stimulated, it pulls on the hair follicle, causing what?
The hair to stand up and cause goosebumps
The skin is also called the...
cutaneous membrane
Shafts of hair are compromised of
dead, keratinized epidermal cells
The dermis is composed largely of
dense irregular connective tissue
Projections of the loose connective tissue from the dermis, which extend upward between the adjacent ridges of the epidermis are called the
dermal papillae
Thin skin is defined by the thickness of the
epidermis
What is the correct order of the layers of the cutaneous membrane?
epidermis, dermis, and hypodermis
What is thin skin?
4 layers of cells
What kind of membrane is the integumentary system?
-Cutaneous membrane
What happens during the proliferation phase?
-Deeper parts of the clot dissolve -Number of capillaries declines -Fibroblasts have formed extensive meshwork of collagen fibers
Why does sagging and wrinkling of the skin occurs as one is aging?
-Due to decrease in elastic fiber network -Integument gets weaker and less resilient
When do apocrine sweat glands become active and what happens?
-During puberty -Secrete into hair follicles in armpits, around nipples, and in pubic region
What area is effected in a second degree burn, symptoms and example?
-Entire epidermis and part of the dermis damaged -Causes blistering, pain, and swelling -Some scar tissue may form
What are some parts of the cutaneous membrane?
-Epidermis -Dermis
What area is effected in a third degree burn, symptoms and example?
-Epidermis and dermis are destroyed -Damage may extend into the hypodermis Sensory nerves destroyed
What is involved in the "Synthesis and storage of nutrients" function?
-Epidermis synthesizes vitamin D3 -Dermis stores lipids in adipose tissue
What skin functions are effected by burns
-Fluid and electrolyte balance -Thermoregulation -Protection from infection
What is involved in the "Excretion and secretion " function?
-Glands excrete salts, water, and organic wastes -Specialized integumentary (mammary) glands secrete milk
What are part of the accessory structures?
-Hair -Exocrine -Nails
What is the hair structure?
-Hair root -Hair shaft
What are some accessory organs?
-Hair shaft -Sweat duct -Sebaceous gland -Sweat gland duct -Hair follicle -Nerve fibers
Where are ceruminous glands located and what do they form?
-Located in passageway of external ear -Forms cerumen, or earwax by combining with sebaceous glands
What are some characteristics of the subcutaneous layer?
-Loose connective tissue beneath the dermis -Separates integument from deeper tissues -Not part of the integumentary system, yet interwoven with connective tissue of the dermis
What happens during the inflammtaion phase?
-Mast cells released at bleeding injury site -Increased blood flow -Increased # of phagocytes
What is the sebaceous gland function?
-Oil gland -Discharge oily lipid secretion (sebum) into hair follicles through holocrine secretion
What area is effected in a first degree burn, symptoms and example?
-Only the epidermis is affected -Causes erythema or redness from inflammation -Example: sunburn
The glands that begin discharging a sticky, cloudy, and potentially odorous secretion at puberty are called what?
Apocrine glands
What is the pigment carotene?
-Orange-yellow pigment -Accumulates in epidermal cells -Found in orange-colored foods (carrots, squashes) -Can be converted into Vitamin A
What layers are in the dermis?
-Papillary layer -Reticular layer
What are the functions of the hair?
-Protect the scalp from U V light -Provide insulation for the skull -Prevent entry of foreign particles into nose, eyes, and ears -Provide early-warning system to prevent injury due to sensory fibers at base of hair follicles
What is involved in the "sensory reception" function?
-Receptors detect touch, pressure, pain and temperature and relay information to nervous system
What happens during the scarring phase?
-Scab is shed and epidermis is complete -Shallow depression marks injury site
Degree of scar formation is dependent on what?
-Severity -Location of injury and age of patient
What is involved in the "protection" function?
-Skin covers and protects underlying tissues -Prevents fluid loss
What is involved in the "Temperature maintenance" function?
-Skin regulates heat exchange with the environment
Why does skin regeneration occur?
-Stem cells of epithelium and connective tissue undergo cell division -Replace lost or damaged tissue
What is the epidermis composed of?
-Stratified (layers) of epithelial cells
How long does hair grow a day?
0.3 mm/day
What are the 2 types of sweat glands?
1. Apocrine sweat glands 2. Eccrine (merocrine) sweat glands
What are the 2 pigments that influence skin color
1. Carotene 2. Melanin
What are the 2 major parts of the integumentary system?
1. Cutaneous membrane, or skin 2. Accessory structures -Hair -Exocrine glands -Nails
What are the 3 layers of dead keratinized cells?
1. Cuticle-surface layer 2. Cortex-middle layer, contains hard keratin 3. Medulla-core , contains soft keratin
What are the 4 phases of skin regeneration?
1. Inflammation phase 2. Migration phase 3. Proliferation phase 4. Scarring phase
What is the order of events for skin repair process?
1. Phagocytosis of pathogens and debris 2. Inflammatory response 3. Formation of scab
What are the 5 functions of the integument system?
1. Protection 2. Temperature maintenance 3. Synthesis and storage of nutrients 4. Sensory reception 5. Excretion and secretion
What are the 2 types of melanin?
1. Red-yellow 2. Brown-black
What are the 2 layers of the cutaneous membrane?
1. Superficial epithelium or epidermis 2. Underlying connective tissue of the dermis
What are the 2 parts of the dermis?
1. Superficial papillary layer 2. Deeper reticular layer
What are the two types of exocrine glands in the integument
1.Sebaceous glands 2.Sweat glands or sudoriferous glands
What are the phases new daughter cells go through that are formed in the stratum basale?
1.Stratum spinosum 2.Stratum granulosum 3.Stratum lucidum Migrate outward toward skin surface
How many types of melanin are there?
2
How long do dead cells stay in the stratum corneum before they shed or are washed away?
2 more weeks
How long does it take for cells to move from stratum basale to stratum corneum?
7-10 days
How thick is the stratum spinosum layer?
8-10 cells thick
What is not a common site of keloid development?
Abdomen
In elderly people, blood supply to the dermis is reduced and sweat glands are less active. This combination of factors would most affect the:
Ability to thermoregulate
The condition that results from clogged sebaceous glands is
Acne
What are causes of sebaceous glands being sensitive to changes in concentrations of sex hormones?
Acne occurs (Blocked sebaceous ducts causes inflammation and raised "pimple")
What does the hypodermis contain?
Adipose tissue Muscle cells Blood vessels Nerve cells
Older individuals do not tolerate summer heat as well as they did when they were young, and they are more prone to heat-related illnesses. What accounts for these changes?
As a person ages, the blood supply to the dermis decreases and merocrine sweat glands become less active
Why does skin sag and wrinkle as a person ages?
As a person ages, the dermis becomes thinner and the elastic fiber network decreases in size, weakening the integument and causing loss of resilience
When do hair cells become keratinized and eventually die?
As hair cells move toward surface. This happens about halfway to skin surface
What is the most common skin cancer?
Basal cell carcinoma
Which of the following conditions is the most common form of skin cancer
Basal cell carcinoma
Why is the stratum basale also called the stratum germinativum?
Because germinative cells are stem cells that continually divide to replace cells lost at the surface
Why can skin regenerate effectively even after considerable damage?
Because stem cells persist in both the epithelial and connective tissue components of skin. When injury occurs, cells of the stratum germinativum replace epithelial cells while mesenchymal cells replace cells lost from the dermis
What happens during the migration phase?
Blood clot or scab forms at surface, to restrict entry of microorganisms
Both dermal layers contain a network of:
Blood vessels (cardiovascular system), lymphatic vessels (lymphatic system), and nerve fibers (nervous system).
What structures help local tissues defend and repair themselves after injury or infection?
Both blood and lymphatic vessels
How is the stratum basale attached to the basement membrane?
By hemidesmosomes
What are the effects of inadequate vitamin D3?
Can lead to weak and flexible bones
Exposure of the skin to UV light
Can slowly increase melanoacyte activity
Which of the following structures is/are associated with the hair papilla?
Capillaries and nerves
What is a pigment found in veggies that can make skin appear orange or yellow
Carotene
What substance is converted to vitamin A, which is required for normal epithelial tissue maintenance?
Carotene
______ is a pigment found in vegetables that can make skin appear orange or yellow
Carotene
Which types of fibers extend from the reticular layer of the dermis into the superficial papillary layer above, as well as into the subcutaneous layer below?
Collagen fibers
What are the 2 major types of tissues that make up the skin?
Connective and epithelial
The dermis consists of what major tissue type?
Connective tissue
What does the stratum spinosum layer consist of?
Consists of keratinocytes held together by desmosomes
What causes your hair to stand/ get "goose bumps"?
Contraction of arrector pili muscle
Where is thin skin found in the body?
Covers rest of the body
The fold of the stratum corneum over the base of a nail is called the
Cuticle
Why do muscles become weaker and bone strength decreases when one is aging?
Decline in Vitamin D3
What is the reason calcium and phosphate absorption decline as we age?
Decreased vitamin D3 production
What are the layers of thick skin?
Deep to superficial Stratum basale (germinativum) Stratum spinosum Stratum granulosum Stratum lucidum Stratum corneum
What is the cutaneous plexus?
Deeper layer that supplies adipose tissue in hypodermis and tissues of the integument
Albinism
Deficiency or the absence of pigment in the skin, hair, and irises of the eyes
The reticular layer of the dermis consists of which tissue level?
Dense irregular connective tissue
The reticular layer of the dermis consists of which tissue type?
Dense irregular connective tissue
What does the severity of burns depend on?
Depth into the tissues and the total area affected
What is NOT an accessory structure of the integumentary system?
Dermal papillae
Epidermal cells are supplied with nutrients from blood vessels in the
Dermis
The highly vascular layer of the skin, which provides thermoregulation via changed blood flow is the
Dermis
As cells are pushed form the deeper portion of the epidermis toward the surface they
Die
Why do identical twins have different finger prints?
Different epidermal ridges
When the body overheats, the skin responds by
Dilating blood vessels
Why is the sensitivity of immune system reduced when one is aging?
Due to a decrease of macrophages residing in the skin
Why does one's hair become thing and changes color when one is aging?
Due to low-functioning follicles and decreased melanocyte activity
Why is one who is aging very sensitive to sun exposure?
Due to lower amount of melanin production
Why does one's ability to lose heat decreases when aging?
Due to reduced dermal blood supply and less active sweat glands
Why does one's skin becomes dry and often scaly when one is aging?
Due to reduction in glandular secretions
Why does one's skin takes more slowly to repair when aging?
Due to slower stem cell division, increasing the threat of infection in cuts
What is the reason for different hair color?
Due to type and amount of melanin from melanocytes
Identify the structures that are responsible for the stretching of the skin during pregnancy
Elastic fibers found in the reticular layer of the dermis
During what repair, would cells divide to produce mobile cells that invade the deeper area of injury?
Fibroblasts and connective tissue stem cell
Fibroblasts create _____ to elevate epidermis
Fibrous, noncellular scar tissue
Why does swimming in fresh water for an extended period cause epidermal swelling
Fresh water is hypotonic with respect to the skin cells, so water moves into the cells by osmosis, causing them to swell
An increase in the rate of malignant melanomas is likely due to which of the following?
Global atmospheric ozone depletion
Stimulation of the arrector pili muscle results in what?
Goosebumps
When the arrector pilli muscles contract
Goosebumps are formed
What term describes the combination of fibrin clots, fibroblasts, and the extensive network of capillaries in healing tissue?
Granulation tissue
During the regeneration process of the skin after injury, what is the combination of blood clot, fibroblasts, and an extensive capillary network called?
Graulosum
Hair is formed by the repeated divisions of epithelial stem cells in which structure?
Hair matrix
The epithelium at the base of a follicle forms a cap over which structure?
Hair papilla
What part of a hair can be seen on the surface of the skin?
Hair shaft
Subcutaneous injections are made in the
Hypodermis
What is another name for the subcutaneous layer?
Hypodermis
What is the subcutaneous layer?
Hypodermis layer that is deep to the dermis -NOT actually part of the integument but stabilizes position of the skin relative to underlying tissues
List the two terms for the tissue that connects the dermis to underlying tissues
Hypodermis or subcutaneous layer
The loose connective tissue that separates the integument from deeper tissues and organs is called the
Hypodermis or subcutaneous layer
The superficial ridges that overlie the dermal papillae
Increase friction and increase skin surface area
Perspiration that is produced by apocrine sweat glands
Is limited to the hair follicles of the axilla, nipples, and groin
What is the function of melanin?
It protects DNA from the damaging effects of UV radiation
Why does hair turn gray or white with age?
Low-functioning follicles and decreased melanocyte activity
The pale crescent area of the nail is called the
Lunula
What is the most dangerous skin cancer?
Malignant melanoma
The observed differences in skin color reflect the levels of what production
Melanin
The reason elderly people are more sensitive to sun exposure and more likely to get sunburned is that with age:
Melanocyte activity declines
The most severe type of skin cancer is most likey to develop from
Melanocytes
Why does exposure to sunlight or sunlamps darken skin?
Melanosomes enter cells of stratum basale, coloring the epidermis
What type of secretion characterizes apocrine sweat glands?
Merocrine
Where does nail growth take place?
Nail root
Why does a superficial cut hurt less than a deep cut?
Nerve fibers are located in the reticular layer of the dermis of the skin
If a burn on the forearm destroys the epidermis and the deep dermis and then heals, will hair grow again in the affected area?
No because the outside layer cuticle, burns away leaving the hair's cortex exposed
Where is thick skin found?
Palms of hands and soles of feet
The superficial layer of the dermis is down as? What is the deep layer?
Papillary layer Deep Layer is the reticular layer
Why does one's hair turns gray or white during older ages?
Pigment production declines with age
The reticular layer's collagen fibers directly provide which function?
Prevent damage to the tissue
Which of the following is the function of hair associated with a nerve fiber?
Provides an early-warning system that may help prevent injury
What is the role of the subpapillary plexus?
Provides blood to capillary loops along epidermis-dermis boundary
What is the layer of the skin that contains bundles of collagen fivers and elastin, and it is responsible for the mechanical strength and flexibility of the skin
Reticular
Microscopically, straight hairs are _________ in cross section, and curly hairs are _________.
Round; flattened
What is used to estimate the burn area?
Rule of Nines (Body surface is divided into multiples of 9%)
The 2 types of exocrine glands in the skin are what?
Sebaceous and sweat glands
What gland secretes into hair follicles?
Sebaceous gland
What is an oil gland that secretes into hair follicles?
Sebaceous gland
Acne results from the blockage of ducts in which glands?
Sebaceous glands
What level of burn is where the superficial and deep cells of the epidermis are affected but the dermis may or may not be affected
Second degree burn
In which level of the classification of burns are the superficial and deep cells of the epidermis affected, whereas the dermis may or may not be affected?
Second degree burns
What is the function of the eccrine sweat gland?
Secretes watery perspiration directly onto surface of skin
Thinning of the epidermis and the decline of stem cell activity leads to which of the following results?
Skin injuries and infections both become more common.
What is the importance of vitamin D3 on the skin?
Skin protection, skin cell growth, repair, and metabolism
The hypodermis...
Stabilizes the position of the skin relative to skeletal muscles and other organs
The deepest layer of cells in the epidermis is the cells of the
Stratum Basale
During the migration phase, what stratum layer cells migrate along wound edges and divide to replace missing cells?
Stratum basale
During wound repair, cells from which layer rapidly divide and begin to migrate along the wound periphery to replace missing epidermal cells?
Stratum basale
The epidermal layer whose cells have stopped dividing and started to produce large amounts of keratin the
Stratum basale
What is the deepest layer of the epidermis?
Stratum basale
The folding over of which integumentary layer forms the cuticle?
Stratum corneum
The layer of the epidermis at the exposed surface is the
Stratum corneum
In which epidermal layer have the cells stopped dividing and begun making large amounts of keratin?
Stratum granulosum
What layer of epidermal do cells stop dividing and have begun making large amounts of keratin?
Stratum granulosum
The layer of the epidermis not present in thin skin is the stratum
Stratum lucidum
What layer of the epidermis is only found in thick skin?
Stratum lucidum (clear layer)
Each time a stem (basal) cell from the stratum basale divides, one of the resulting daughter cells enters which of the following layers?
Stratum spinosum
Upon exposure to ultraviolet radiation, cells in which two epidermal layers convert a steroid into vitamin D3?
Stratum spinosum and basale
What regions changes the most in response to circulating levels of sex hormones?
Subcutaneous layer (hypodermis)
Squamous cell carcinoma involves what?
Superficial epidermal cells
Blood supply in the dermis is supplied by what?
Supplied by networks of arteries called plexuses
What is the role of the papillary layer?
Supports and nourishes epidermis
What is the reason for skin to turn a pale color?
Temporary constriction of the same blood vessel
When a person becomes "pale", what is the physiologic basis?
The blood supply to the skin decreases
When a person becomes "pale," what is the physiologic basis?
The blood supply to the skin decreases
The excessive production of keratin is called hyperkeratosis. Calluses and corns are easily observed examples of hyperkeratosis. What epidermal layer is characterized by cells that have stopped dividing and have begun making large amounts of keratin?
The stratum granulosum, consists of cells displaced from the stratum spinosum that have stopped dividing and have begun making large amounts of the protein keratin.
Why are injections administered in the hypodermis when administering drugs using a hypodermis needle?
There are no vital organs in the region
As cells are pushed from the deeper portion of the epidermis toward the surface,
They die
What are keloids?
Thickened areas of scar tissue covered by shiny, smooth epidermal surface
The type of burn that injures the hypodermis, deeper tissues, and organs is
Third degree burn
What type of burn cannot repair themselves and requires skin grafting?
Third degree burn
What burn destroys the epidermis as well as the hair follicles?
Third-degree burn
What amino acid is melanin produced by?
Tyrosine
Melanin serves to protect cells in the deeper layers of the epidermis from
UV radiation
The epidermis synthesizes what?
Vitamin D3
Why do calluses form?
When skin is subjected to mechanical stress, stem cells in the stratum basal divide more rapidly and the thickness of the epithelium increases
Why does hair turn gray or white with age?
With advancing age, melanocyte activity decreases, leading to gray or white hair
The subcutaneous layer consists of
areolar and adipose tissue
Squamous cell carcinoma involves
superficial epidermal cells