Ch.5 Integumentary System
Describe the effect of UV exposure on the skin.
Increased melanin synthesis
The integumentary system functions include all of the following except
production of calcium.
As cells fill with keratin, the deep cuboidal cells change shape and become flat.
true
Carotene imparts a ______ color to healthy skin.
yellow
Expanded knob at the base of the hair root
hair bulb
Contains the hair; consists of epithelial and dermal root sheaths
hair follicle
Protrudes above the surface of the skin
hair shaft
1. Name the layers of hair on the cross-section
a. Hair Follicle b. Hair Bulb c. Dermal Papilla d. Arrector Pili Muscle e. Sebaceous (Oil) Glands
The layers of the skin include the ______, which is the most superficial, and the ______, which is deeper.
epidermis, dermis
When body temperature starts to rise above normal, the eccrine sweat glands produce sweat which ______.
evaporates and cools the body
The skin appears orange or yellow.
High levels of carotene are present.
What type of tissue makes up the epidermis?
Epithelial tissue
What is the function of hypodermis?
The hypodermis contains the cells known as fibroblasts, adipose tissue (fat cells), connective tissue, larger nerves and blood vessels, and macrophages, cells which are part of the immune system and help keep your body free of intruders.
Name 2 main parts of hair; where is each one located?
An epithelial root shaft which is located above the skin surface i. Includes hair bulb with wide part at the base of root A dermal root shaft located below the level of the skin
Explain the steps of a skin wound healing (epidermal and dermal) and scar formation.
Basal epithelial cells on the edge of the wound detach from the basement membrane, migrate into the wound, and enlarge to form a clot Other edge cells slide along into the wound as a sheet Epidermal; growth factor stimulates stem cells to divide and replace the migrating cells. When the migrating cells meet, they stop moving (contact inhibition) grow, and build new strata therefore completing the wound repair.
Develop in people who are bedridden and have compression of tissue and reduced circulation resulting in destruction of the subcutaneous tissue and skin; areas later become infected by bacteria.
Decubitus ulcers
Inflammatory condition of the skin caused by allergy, infection, poor circulation, or exposure to chemicals
Eczema
True or false: Melanocytes are the only darkly pigmented cells in the epidermis.
False
the accessory skin structures.
Hair Nails Glands
The skin appears brown or black.
High proportions of melanin are deposited in the skin.
Small blisters containing pus; easily rupture to form a thick, yellowish crust; usually affects children
Impetigo
Exposure to sunlight leads to which of the following?
Increased melanin production and darkening of the skin
List the differences and similarities between thin and thick skin. Where on the body can you find each type of skin?
List the differences and similarities between thin and thick skin. Where on the body can you find each type of skin?
Within melanocytes, the Golgi apparatuses package melanin into vesicles called melanosomes (MEL-ah-no-sohms).
Melanosomes move into the cell processes of the melanocytes. Epithelial cells phagocytize the tips of the melanocyte cell processes, thereby acquiring melanosomes. Although all the epithelial cells of the epidermis can contain melanin, only the melanocytes produce it.
List all functions of the skin.
Physical barrier i.e. mechanical, infection Water barrier Thermoregulation and insulation Sensation i.e. temperature, tactile, and pain Vitamin D synthesis which requires sunlight Waste excretion through the sweat glands Absorption i.e. hydrophobic drugs like patches Appearance and communication such as facial expressions & hair
Chronic skin disease characterized by thicker than normal epidermal layers that sloughs to produce large, silvery scales
Psoriasis
What is the function of sebaceous glands and where in the skin are they located?
Sebaceous gland, small oil-producing gland present in the skin of mammals. Sebaceous glands are usually attached to hair follicles and release a fatty substance, sebum, into the follicular duct and thence to the surface of the skin.
Part of the hair above the surface of the skin
Shaft
Follicle
Surrounds the part of the hair below the surface of the skin
The accessory skin structures include ha
The accessory skin structures are hair, glands, and nails.
Which cells in the epidermis are responsible for immune response?
a. Langerhans Cells are immune cells that originate in the red bone marrow, involved in the defense against infections.
Explain how skin color is determined and which pigments and cells are involved.
a. Melanin content of skin is the main determining factor of skin and hair color; b. hair is considered a form of skin with regards to pigmentation. Melanin is synthesized by melanosomes found in skin cells called melanocytes.
What are two types of sweat glands and where is each type located?
a. Your skin has two types of sweat glands: eccrine and apocrine. i. Eccrine glands occur over most of your body and open directly onto the surface of your skin. ii. Apocrine glands open into the hair follicle, leading to the surface of the skin.
The dermis is immediately deep to the ______ of skin
epidermis
What is the tissue origin of melanocytes?
originate from the "neural crest"
A deficiency of _______ causes a blueness of the skin called
oxygen, cyanosis
Touch receptors of the skin are located in all of these areas
-around the base of the hair follicle -in the dermis -in the dermal papillae -in the epidermis
What is albinism and what causes it?
Albinism is a genetically recessive condition (meaning that the trait skips generations) characterized by inability to make melanin. Result of not being able to make melanin is a lack of pigmentation in the skin hair It is said that people with this condition are normal mentally and physically but are more prone to sunburn and skin cancer
Where (in which layer) are melanocytes located in the epidermis and what is their function?
Melanocytes are present in the superficial stratum basale layer Melanocytes produce dark pigment molecule melanin, that produces keratinocytes from UV light damage.
What is the function of arrector pili? What type of tissue are they made of?
The arrector pili muscle (APM) consists of a small band of smooth muscle that connects the hair follicle to the connective tissue of the basement membrane. The APM mediates thermoregulation by contracting to increase air-trapping, but was thought to be vestigial in humans.
A mother of a toddler visits her pediatrician because her child is turning orange. Lab tests indicate no abnormality. What could be causing the orange coloration? Multiple choice question.
The toddler's diet consists of mostly sweet potatoes and carrots.
How would you distinguish an epidermal cut from a deeper (dermal) cut?
There are two types of wounds which depend on the depth of the injury i. Epidermal (superficial) 1. One could distinguish this particular wound by the bleeding or actually the lack of bleeding. These wounds affect only the epidermis and do not bleed because the epidermis is avascular will heal completely leaving no scar behind. 2. Even know the epidermis is avascular it dies have pain receptors which will cause the cut to be painful 3. Due no the epidermis being avascular means no cut in the dermis area means that there won't be any scaring. i.e. perfect scaring. ii. Dermal (deep)
What is the role of UV light in skin aging and how does skin protect itself against it?
UV light stimulates the production of melanin UV light from the sun is currently the main cause of skin aging UV light causes DNA damage resulting sunburn, wrinkles, spots, sagging and skin cancer d. The skin uses sunlight to help manufacture vitamin D, which is important for normal bone formation e. Melanin protects skin from the sun's ultraviolet rays. These can burn the skin and reduce its elasticity, leading to premature aging
Which sweat gland produces pheromones and what is their function?
a. Apocrine glands produce viscous, lipid-rich sweat, which is also comprised of proteins, sugars, and ammonia. b. The function of apocrine glands in many species is generally regarded as scent glands involved in production of pheromones (body odor), although this social/sexual function is rudimentary in humans.
Which type of cells makes hair grow?
a. Hair follicle stem cells are long-lived cells in the hair follicle; they are present in the skin and produce hair throughout a person's lifetime. They are "quiescent," meaning they are normally inactive, but they quickly activate during a new hair cycle, which is when new hair growth occurs.
Describe tissue composition of the dermis.
a. inner layer of the skin b. consists of superficial and papillary layer c. composed of connective tissue proper d. mainly collagen fibers (elastic and reticular still present) e. contains motile cells called dendritic cells just as the epidermis dendritic cells f. serve an immune function in the dermis
When a dark pigment, such as seen in a tattoo or bruise, is within the dermis or subcutaneous tissue, the pigment appears
blue
The dermis is comprised primarily of ______ tissue.
connective tissue
the skin appears blue
dark pigment is located in the dermis or subcutaneous tissue
The most superficial layer of skin is the ______.
epidermis
Identify the components of the integumentary system
hair nails glands skin
List the strata of the epidermis from the deepest layer to the most superficial.
stratum basale intermediate strata startup corneum
The dermis contains receptors that detect ______
touch pain changes in pressure variations in temperature
1. Name all sensory receptors found in the skin. In which layer is each located and what sensations does each perceive?
General principle is that if a receptor is closer to the surface of the skin, they are for light touch. i. Merkel cells in the stratum basale of epidermis ii. Meissner corpuscles in the papillary layer of the dermis. iii. Ruffini corpuscles are in the middle of dermis and respond to dermis stretching or twisting. iv. Pacinian corpuscles are in deep dermis and hypodermis and respond to deep pressure or vibration.
3. Fungal infection that produces patchy, scaling and inflammatory response in the skin.
Ringworm
Name the conditions of abnormal skin color changes. What are their causes?
Skin color changes can be used for diagnostics i. Cyanosis is deoxygenated hemoglobin which skin appears blue in color ii. Erythema is redness caused by vasodilation in dermis such as heat, mechanical stimuli i.e. massage, and or even inflammation iii. Pallor is paleness due to vasoconstriction in dermis i.e. in cold weather or severe anemia (low iron levels) iv. Jaundice is yellow pigment bilirubin which is normally removed by liver. Usually a symptom of liver disorders and or disease. v. Hematoma (bruise) is a decomposing hemoglobin
One function of the skin is excretion. Indicate the compounds excreted in small amounts via sweat.
Urea Ammonia salts
Explain what "keratinization" is and why it is important.
a. Keratinization is important because keratin is a tough, fibrous, waterproof protein that gives skin its resiliency & strength. b. The majority of cells in the epidermis are keratinocytes. Keratinocytes located along the basement membrane are well nourished by the blood supply of the underlying dermis, therefore these cells can grow & divide. When new daughter cells are produced, they push older cells away from the life-sustaining nutrients of the dermis toward the outer layers of the epidermis. As older cells travel from the basal to the superficial layers, they undergo profound changes: they fill with keratohyalin granules; loses their nuclei, cytosol & organelles; & ultimately become lifeless sheets of keratin. This process is called keratinization & enables millions of dead cells rub off or "exfoliate" daily
What are the dermis structures that make attachment between dermis and epidermis stronger and contribute to fingerprint pattern?
a. The papillary region is composed of loose areolar connective tissue. It is named for its finger-like projections called papillae, which extend toward the epidermis. The papillae provide the dermis with a "bumpy" surface that interdigitates with the epidermis, strengthening the connection between the two layers of skin. The ridges cause ridges in the overlying epidermis, called epidermal ridges. Thoseridges and the sweaty marks they leaveare what we call fingerprints
One factor in determining skin color is the thickness of the stratum
corneum
Forms the bulk of the hair; consists of cells containing hard keratin
cortex
Which factor does not determine skin color?
keratin deposition
If you take a cold shower, the blood vessels in the dermis will ______ in order to maintain homeostasis.
constict
Outer layer of the hair; single layer of cells containing hard keratin
cuticle
When the blood vessels in the dermis constrict, blood from from the deeper tissues to the dermis decreases; therefore, heat loss from the body
decreases
Dark brown to black pigmentation of the skin results from ______.
deposition of melanin by melanocytes
The connective tissue layer immediately deep to the epidermis is the ______.
dermis
The deeper layer of skin is the ______.
dermis
The structural strength of the skin is predominantly the responsibility of the __________.
dermis
When you are hot, blood vessels in the dermis _____ in order to maintain homeostasis.
dilate
Sweat glands that are simple, coiled, tubular glands opening directly onto the surface of the skin of the palms of the hands and the soles of the feet through sweat pores are __________ sweat glands.
eccrine
Name two main layers of the skin and specify the tissues that each one is made of.
epidermis, made of closely packed epithelial cells dermis, made of dense, irregular connective tissue that houses blood vessels, hair follicles, sweat glands, and other structures
Keratin is a lipid, which limits water loss through the skin
false
The most superficial layer is the stratum basale and the dead squamous cells are filled with keratin.
false
Burns that result in redness, pain and edema but do not blister are classified as
first degree burns
The sockets that originate in the dermis and surround hair are the hair ______.
follicles
Which of the following is part of the integumentary system?
hair and nails
Melanin is produced by
melanocytes (MEL-an-oh-cytes; melano, black + kytos, cell). Melanocytes are irregularly shaped cells located between the stratum basale and the stratum spinosum. They have many long processes that extend between the epithelial cells of the deep part of the epidermis.
Basal Cell Carcinoma
most common type of skin cancer, varied appearance but often ulcer- like and may be red with some bleeding
The features of intact skin that reduce water loss include ______.
multiple layers of dead skin cells in stratum corneum epidermal lipids presence of many epidermal and dermal layers the keratin-filled cells of the epidermis
One of the most important functions of melanin is to ______.
provide protection against ultraviolet light from the sun
One function of the skin is excretion. Indicate the compounds excreted in small amounts via sweat.
salts Ammonia Urea
In addition to surrounding the hair root, another function of the hair follicle is to ______.
serve as a source of new epithelial cells for damaged epidermal tissue
Vitamin D
stimulates calcium and phosphate uptake in the small intestine. is formed from a precursor molecule that is made when skin is exposed to ultraviolet light. is formed from a precursor molecule that is modified in the liver and kidneys. may be required in the diet if a person is exposed to very little ultraviolet light
The epidermis consists of ______ squamous epithelial tissue.
stratified
The organs of the integumentary system have several functions. Which component best serves as thermal insulation?
subcutaneous layer
All the epithelial cells of the epidermis can contain melanin, but only the ______ produce it.
melanocytes
The cells contributing to skin color are the ______.
melanocytes
Central axis of the hair
medulia
The group of pigments known collectively as is responsible for protecting skin cells from UV damage.
melanin
Regeneration of the epidermis in a second-degree burn
Both "comes from epithelial cells with the hair follicles and sweat glands" and "comes from epithelial cells at the edges of the damaged area " are correct.
The deposition of which substance is primarily responsible for the color of the skin, hair and eyes?
Melanin
Which of the following cells produce a pigment found in the skin?
Melanocytes
Identify the item that is NOT a function of subcutaneous fat. Multiple choice question.
Production of vitamin D the following are a function of subcutaneous fat; thermal insulation energy reserve cushioning of bony structures
Part of the hair below the surface of the skin
Root
Name the oily component of the secretion of the sebaceous glands.
Sebum
How many layers are there in the epidermis? Name each in order from superficial to the deep and briefly describe their distinctive features.
Stratum Corneum top layer of dead cells 5 to 50 cells which are extremely thin and flat cells that are filled with keratin and have no organelles and are constantly shed and replaced from deeper layers. Stratum Lucidum 4 to 6 layers of keratin - filled translucent cells which are more compact keratin and developed more in thick skin. These cells are dead cells. Stratum Granulosum 3 to 5 layers with granules of keratahyalin and lamellar granules i.e. lipids. This layer is called the waterproof layer of skin and the cells are dying. Stratum Spinosum is 8 to 10 layers thick at this level keratin is starting to be produced with desmosomes and bundles of keratin that make the layer look spiky. Some of the cells in this layer may still divide. Stratum Basale is the deepest layer with one layer of cells attached to the basement membrane. These are the skin stem cells and provide replacement cells for all of the other layers.
The skin becomes tan.
There is an increase in melanin production due to UV radiation exposure.
Which two statements describe melanocytes?
They have long processes that extend between the epithelial cells in the deep part of the epidermis. They are irregularly shaped cells that produce melanin.
The most superficial layer is the stratum corneum and the dead squamous cells are filled with keratin.
True
True or false: If the epidermis is damaged, the undamaged part of the hair follicle within the dermis can be a source of new epithelium.
True
Albinism is ______.
a genetic trait
Melanoma
large flat spreading or a dark nodule. most deadly type of skin cancer as metastasis is common. arise from melanocytes.many develop from preexisting moles.
What is the name of the most common cell type of the epidermis?
a. Keratinocytes are the predominant cell type of epidermis and originate in the basal layer, produce keratin, and are responsible for the formation of the epidermal water barrier by making and secreting lipids.
An individual that has a higher deposition of melanin in the skin would most likely
have darker skin
An individual that has a higher deposition of melanin in the skin would most likely ______.
have darker skin
The symptoms of first degree burns ______
heal in a week or so without scarring may result in redness, pain, and slight edema or swelling
Indicate the stimuli for the sweat produced by the eccrine glands of the skin.
increased body temperature emotional stress
When blood vessels in the dermis dilate and promote blood flow from the deeper tissues to the skin, the result is that heat loss from the body
increases
When the skin is flushed, the amount of heat loss ______.
increases
The skin and accessory structures such as hair, nails and glands form the system.
integumentary
melanin
is the group of pigments primarily responsible for skin, hair, and eye color.Most melanin molecules are brown to black pigments, but some are yellowish or reddish. Melanin provides protection against ultraviolet light from the sun.
An accumulation of bile pigments in tissue can lead to a yellowish skin color, called ______________ This can occur when the liver is damaged by a disease, such as
jaundice
As cells fill with keratin, they create intermediate strata and begin to die.
true
Squamous CellCarcinoma.
typically contained to the epidermis, but left untreated can invade the dermis. often scaled, raised, or a wart-like growth with a depression
Touch receptors of the skin are located in all of these areas, except ______.
within the hair of the dermis and epidermis.
