Chapter 51: Structure and Function of the Skin

An adolescent, who is an athlete, asks the health care provider, "Why do I now have such awful body odor? What has changed in my body?" Which response is the best reply? "Apocrine sweat glands open through a hair follicle and secrete an oily substance that mixes with bacteria on the skin, producing body odor." "As one develops more muscles and are able to work out longer and harder, more sweat mixes with body secretions making up 'body odor.'" "This is just a sign that you need to thoroughly wash and dry your skin, especially under your arms and your groin, more carefully." "Hormones, like androgens and testosterone change the chemicals in your body making it smell worse when one sweats."

"Apocrine sweat glands open through a hair follicle and secrete an oily substance that mixes with bacteria on the skin, producing body odor." Apocrine sweat glands open through a hair follicle and secrete an oily substance that mixes with bacteria on the skin, producing body odor. Bathing is not the cause since it is caused by increased sweat during exercise. The exercises produces more sweat, it is not because the muscles have more fully developed. The change in hormones are not the reason for body odor, even though the hormones do change at puberty.

A child arrives to the outpatient clinic with a high fever of 103°F (39.5°C). The parents have the child wrapped in many blankets to "keep them warm, since the child is shivering." What is the rationale for the health care provider to educate the parents that less blankets will help the child more? "We know you want to keep your child comfortable, but blankets will not help lower your child's fever." "Since your child is not coughing or throwing up, I think you just need to take him home and give him liquid acetaminophen." "Fever dilates vessels and results in sweating, the purpose of the eccrine sweat glands. Too many blankets are counterproductive and will actually help the temperature to go higher." "Let's remove the blankets and place ice packs under your child's arms instead."

"Fever dilates vessels and results in sweating, the purpose of the eccrine sweat glands. Too many blankets are counterproductive and will actually help the temperature to go higher."

A nursing instructor is teaching students about skin structure. The instructor evaluates student knowledge of the epidermis based on which statement? "The epidermis is a connective tissue layer that separates the dermis from the underlying subcutaneous fat layer." "The epidermis is thinnest on the palms of the hands and soles of the feet than elsewhere on the body." "Keratinized epithelial cells formed in the deepest layer of the epidermis migrate to the skin surface to replace cells that are lost during normal skin shedding." "The epidermis contains the blood vessels and nerve fibers that feed the skin cells."

"Keratinized epithelial cells formed in the deepest layer of the epidermis migrate to the skin surface to replace cells that are lost during normal skin shedding."

A client arrives with a very large blister on the heel from "new shoes" and fear having "damaged" the structures (ligaments and tendons) beyond repair and want to know "what caused this blister?" Which nursing response is best in this situation? "This damage is only on the epidermis layer which is the top layer of your skin. No underlying structures are damaged." "This blister should be aspirated so that we can put some antibiotic cream on it and a bandage. You should not wear any shoes with a back until it is completely healed." "This blister is caused by mechanical friction from repeated rubbing on this area. The fluid is in the basement membrane between the epidermis and dermis." "If you can still control movement of your foot, then that means no important structures are damaged. It just takes some time for healing to occur."

"This blister is caused by mechanical friction from repeated rubbing on this area. The fluid is in the basement membrane between the epidermis and dermis."

A client shows the nurse an area on his arm where he has repeatedly been giving insulin injections to himself. The nurse feels the area and the skin appears to be thin. The nurse feels a "valley" or indentation in the area. What would the nurse tell the client? "This is a scar." "This is an area of hypertrophied skin." "This is an area of atrophy." "This is a keloid."

"This is an area of atrophy." The area of skin that feels like an indentation is most likely lipoatrophy or atrophied skin due to repeated insulin injections. A hypertrophied area would feel like a "lump." A scar is an actual mark left from a healing wound.

A client reports having pruritus. Which question is most appropriate for the nurse to ask first? "Do you have a lesion in the area?" "Where do you feel itching?" "Did you hit anything?" "Are you on any new medications?"

"Where do you feel itching?" The first thing the nurse should ask is where the itching is occurring. The nurse could then inspect the area. Itching is not necessarily caused by being hit or having a lesion. Asking if the client is on new medications is not particularly helpful, as itching can have many causes. The nurse should first assess the area.

The parent of a infant recently diagnosed with albinism asks, "Why did this happen to my infant?" Which response by the nurse is most appropriate? "Your infant is not producing the enzyme tyrosinase, which is needed to synthesize melanin. Melanin protects the skin from UV rays and adds color to the skin." "Your infant just needs to have some sunlight. Then the skin will begin to produce a pigment called melanin and your infant will get some color in the skin." "Without any keratinocytes of the epidermis, the skin has no protection or color. Don't worry, your child will grow up to happy and healthy like peers." "Does anyone in your or your partner's family have this condition? That might help explain why this infant has developed this."

"Your infant is not producing the enzyme tyrosinase, which is needed to synthesize melanin. Melanin protects the skin from UV rays and adds color to the skin." Melanocytes produce a pigment called melanin, which is responsible for skin color, tanning, and protection against ultraviolet radiation. Albinism is inherited. There is a normal number of melanocytes, but little to no tyrosinase, the enzyme needed for synthesis of melanin. It affects the skin, hair, and eyes.

Which structure would likely be present in a hair follicle in a man's groin but not in a follicle on his face? Apocrine gland Arrector pili muscle Hair papilla Sebaceous gland

Apocrine gland Apocrine glands are only found in hair follicles in the underarms and groin. All hair follicles contain an erector pili muscle, sebaceous gland, and blood supply in the form of the hair papilla.

Which characteristic differentiates apocrine sweat glands from eccrine sweat glands? Apocrine glands are primarily thermoregulatory. Apocrine secretions help maintain skin pH. Apocrine glands are more numerous and widely distributed than eccrine glands. Apocrine secretions contain oils.

Apocrine secretions contain oils. The major difference between apocrine glands and the eccrine glands is that apocrine glands secrete an oily substance. Apocrine glands are less widely distributed than eccrine glands, and they do not contribute as significantly to thermoregulation. Neither is a major contributor to skin pH.

The nurse is caring for a group of clients in their 80s. How can the nurse best prevent skin tear injuries while caring for these clients? Provide optimal nutrition and hydration status. Apply emollient lotions regularly after bathing. Avoid manipulation that causes traction on the skin. Ensure the client wears loose-fitting, unrestrictive clothing.

Avoid manipulation that causes traction on the skin. Skin tears result due to the loss of anchoring between the skin layers that occurs due to aging. This places the aging person at risk for shearing injuries when traction is applied to the skin (e.g., when a client's skin is dragged against a bed sheet when repositioning). Good nutrition and moisturizing techniques can help with dry skin and wound healing but will not prevent skin tears. Loose-fitting clothing is not as important as avoiding shearing forces when trying to prevent skin tears.

A 70-year-old client has needed to reduce the frequency of bathing due to dry skin. Which factor has resulted in this age-related change in skin function? Change in composition of sebaceous secretions Slower keratinization Increased production of bile salts Dehydration of epidermal cells

Change in composition of sebaceous secretions The effects of aging on skin dryness include a change in the composition of sebaceous gland secretions and a decrease in the secretion of moisture from the sweat glands. Changes in the composition of keratinocytes and the process of keratinization do not account for the drier skin that accompanies aging. Deposition of bile salts on the skin surface causes pruritus and dry skin, but this is a pathologic process rather than an age-related change.

Which definition of a plaque is most accurate? Flat, flaky, whitish, detachable fragment of epidermis Elevated, coalesced papules >0.5 cm Small, flat discolored lesion Encapsulated, fluid-filled mass

Elevated, coalesced papules >0.5 cm Plaque may be coalesced papules greater than 0.5 cm. Small, flat discolored lesion is a macule patch. Encapsulated, fluid-filled mass is a cyst. Flat, flaky, whitish, detachable fragment of epidermis is related to dandruff, psoriasis, or dry skin.

Which factor is genetically determined and primarily responsible for dark skin tone? Superficial distribution of melanocytes High production of melanin Dense distribution of melanosomes High levels of tyrosinase

High production of melanin Although the number of melanosomes in dark and light skin is the same, dark skin produces more melanin, and more quickly, than light skin. Dark-skinned persons do not possess a more superficial distribution of melanocytes or increased levels of tyrosinase.

A parent calls the health care provider reporting the child has red sores on the face, especially around the nose and mouth that have pus/fluid inside and when the sores burst, they develop a honey-colored crust. The parent is asking whether to make an appointment. Which contagious skin lesion does the provider think the child has developed? Poison ivy Herpes simplex Impetigo pustule Sebaceous cyst

Impetigo pustule Impetigo is a form of pustule and is primarily described as red sores on the face, especially around a child's nose and mouth, and on the hands and feet. The sores burst and form honey-colored crusts. This is the classic description of impetigo. A vesicle is less than 0.5 cm, circumscribed, elevated, and a palpable mass containing serous fluid. It may be cause by herpes simplex, a cold sore. Poison ivy develops after exposure to the plant out-of-doors and is described as circumscribed, elevated, palpable masses containing serous fluids. Poison ivy usually is a red, itchy rash with swelling, bumps and blisters that can spread by contact. A sebaceous cyst is an encapsulated, fluid-filled or semisolid mass in the subcutaneous tissue and is not considered contagious.

A 40-year-old male client has a congenital syndrome that affects the function of the Langerhans cells of his epidermis. The man's care provider would expect which manifestation of his condition? Frequent separation between the dermal and epidermal layer of his skin High permeability of his epidermis to environmental materials Increased susceptibility to infection Lighter skin tone than other individuals of the same ethnicity

Increased susceptibility to infection Langerhans cells are the immunologic cells responsible for recognizing foreign antigens harmful to the body. They play an important role in defending the body against foreign antigens. A lack of Langerhans cells would not manifest in increased permeability of the skin, unexpected coloration, or separation between layers.

A client has dry skin, and scratching the dry regions causes some skin flakes to become dislodged. Which cell type makes up the dry skin? Keratinocytes Melanocytes Merkel cells Langerhans cells

Keratinocytes The keratinocyte is the major cell of the epidermis, comprising 95% of the cells of this layer. The epidermis is composed of stratified squamous keratinized epithelium. Melanocytes produce pigments, Merkel cells are sensory cells, and Langerhans cells are immune cells.

What is a physiologic basis for albinism? Lichenification Accelerated keratinization Lack of tyrosinase Separation of the epidermis from the dermis

Lack of tyrosinase Although there are more than 10 different types of albinism, the most common type is recessively inherited oculocutaneous albinism, in which there is a normal number of melanocytes but they lack tyrosinase, the enzyme needed for synthesis of melanin.

A student with a rash goes to the school nurse for evaluation. The nurse suspects the student has contact dermatitis. The primary cell responsible for this delayed-type hypersensitivity reaction is: Reticular dermis Langerhans cells Dermal dendrocytes Merkel cells

Langerhans cells As antigen-presenting cells, the Langerhans cells are involved in delayed-type hypersensitivity reactions such as contact dermatitis and other cell-mediated immune responses in the skin; their dendritic processes extend through keratinocytes, forming a network to bind and process antigen. Merkel cells provide sensory information to the skin. In the dermis, the reticular dermis is a complex meshwork of three-dimensional collagen bundles that contain dermal dendrocytes, which have phagocytic properties.

A nursing instructor is teaching students about skin structure. The instructor evaluates student knowledge of the Langerhans cells based on which statement? Langerhans cells are a layer of intercellular and extracellular matrices that serves as an interface between the dermis and the epidermis. Langerhans cells are the immunologic cells responsible for recognizing foreign antigens harmful to the body. Langerhans cells are involved in relaying signals between the skin systems. Langerhans cells serve as touch receptors.

Langerhans cells are the immunologic cells responsible for recognizing foreign antigens harmful to the body. Langerhans cells are scattered in the suprabasal layers of the epidermis among the keratinocytes. Langerhans cells are the immunologic cells responsible for recognizing foreign antigens harmful to the body. Langerhans cells play an important role in defending the body against foreign antigens.

A client comes to the clinic with a "terrible itch" on the abdomen and waist that has lasted for several months and has been scratched continuously. Inspection reveals an area of thickened rough skin. The nurse documents this condition using which term? Keloid Lichenification Keratosis Fissure

Lichenification Repeated rubbing and scratching can lead to lichenification (thickened, leathery, and roughened skin characterized by prominent markings).

The health care provider has just completed a skin assessment on a client. The client asks what causes the numerous freckles that she has. The best response is: If you develop freckles, you will note develop moles. Localized collections of eumelanin contribute to the development. They are inherited. They are more prominent in males rather than females.

Localized collections of eumelanin contribute to the development. Exposure to the sun's ultraviolet rays increases the production of eumelanin, a brownish black pigment, which causes tanning to occur. The primary function of such melanin is to protect the skin by absorbing and scattering harmful ultraviolet rays, which are implicated in skin cancers. Localized concentrations of eumelanin are also responsible for the formation of freckles and moles.

A client expresses concern to the nurse about an area of skin on the chest that has recently turned white and was diagnosed as vitiligo. Which principle best explains the cause of vitiligo to the client? Vitiligo is a bacterial infection that can be treated with an ointment. Melanocytes are destroyed, leading to a complete absence of melanin pigment. There is an increased production of eumelanin. Smaller amounts of melanosomes are being produced due to aging.

Melanocytes are destroyed, leading to a complete absence of melanin pigment. Vitiligo is the complete absence of melanin pigment in patchy areas of white or light skin on the face, neck, hands, feet, body folds, and around orifices—otherwise the depigmented skin is normal.

A client has sought care for a serious sunburn that resulted from falling asleep at the beach. What physiologic process was involved in the client's overexposure to ultraviolet radiation? The client's keratinocytes became overwhelmed by radiation Merkel cells became inflamed from excessive sun exposure Melanocytes were unable to sufficiently protect that client The Langerhans cells produced an adaptive response

Melanocytes were unable to sufficiently protect that client Melanocytes produce a pigment called melanin that is responsible for skin color, tanning, and protecting against ultraviolet radiation. Keratinocytes in the epidermis provide external strength and protection. Merkel cells provide sensory information. Langerhans cells link the epidermis to the immune system.

Which are the sparsest cells in the epidermis? Merkel cells Melanocytes Pigment cells Keratinocytes

Merkel cells Merkel cells are clear cells found in the stratum basale of the epidermis. They are the sparsest cells in the epidermis. The other cells appear in higher numbers throughout the body.

Select the cells of the epidermis that are responsible for providing sensory information. Keratinocytes Melanocyte cells Langerhans cells Merkel cells

Merkel cells The Merkel cells provide sensory information. Langerhans cells link the epidermis to the immune system, melanocytes provide pigmentation to the skin, and keratinocytes provide a protective function to the skin.

A preschooler asks the parents at bath time, "Why are my nipples red?" Which form of melanin is responsible for the coloring of nipples and lips in humans? Desmosomes Pheomelanin Keratinocytes Eumelanin

Pheomelanin Pheomelanin, the yellow to red pigment, is found in all humans. It is particularly concentrated in the lips, nipples, glans penis, and vagina. Eumelanin is abundant in humans. Exposure to the sun's rays increases the production of eumelanin, causing tanning to occur. A desmosome, also known as a macula adherens, is a cell structure specialized for cell-to-cell adhesion. Keratinocytes produce keratin, a complex protein that forms the surface of the skin and is also the structural protein of the hair and nails. Keratinocytes are now known to be active secretory cells that play an important role in the immunobiology of the skin by communicating and regulating cells of the immune response and secreting cytokines and inflammatory mediators.

While studying the skin in a science class, a student asks why all people have a pinkish color to their lips/mucous membranes. The instructor would respond by stating: A person with tiny melanocytes will have more concentrated pigment resulting in darker color. Melanocytes are the pigment-synthesizing cells. Tyrosinase is responsible for all colored cell production. Pheomelanin is the yellow to red pigment particularly concentrated in the lips and nipples in humans.

Pheomelanin is the yellow to red pigment particularly concentrated in the lips and nipples in humans. Pheomelanin, the yellow to red pigment, is found in all humans. It is particularly concentrated in the lips, nipples, glans penis, and vagina. Melanocytes are pigment-synthesizing cells that are scattered in the basal layer and are responsible for skin color (not mucous membranes). Tyrosinase converts the amino acid tyrosine to a precursor of melanin. If a person lacks tyrosinase, the end result will be albinism. In dark-skinned people, larger melanin-containing melanosomes are produced and transferred individually to the keratinocyte.

The nurse is assessing a client who has a small pinpoint rash. What is the best cause of this rash? Purpuric lesions Macular papular lesion Pinpoint petechiae Pinpoint lesions

Pinpoint petechiae Small pinpoint spots are usually petechiae. Lesions are traumatic or pathologic loss of normal tissue structure and would not be appropriate to document as a rash.

Select the layer of dermis characterized by a complex meshwork of three-dimensional collagen bundles interconnected with large elastic fibers. Papillary dermis Reticular dermis Epidermis Subcutaneous tissue

Reticular dermis The reticular dermis is a complex meshwork of three-dimensional collagen bundles interconnected with large elastic fibers and is the thicker area of the dermis, which forms the bulk of the dermal layer. The papillary layer of the dermis is a thin superficial layer that interdigitates directly with the epidermis.

A client has a small blister on the left heel. The nurse documents this as a vesicle. What is an appropriate definition? Collection of small blood vessels Linear, cracklike defect Small abscess Small, fluid-filled sac

Small, fluid-filled sac A vesicle is a circumscribed, elevated, palpable mass that is >0.5 cm containing serous fluid.

Mitosis that results in the production of new epidermal cells occurs in which layer of the epidermis? Stratum granulosum Stratum germinativum Stratum lucidum Stratum spinosum

Stratum germinativum The deepest layer of the epidermis, the stratum germinativum (sometimes referred to as stratum basale), consists of a single layer of basal cells that are attached to the basal lamina in the basement membrane. The basal cells are the only epidermal cells that are mitotically active.

Most of the skin's blood vessels are innervated by which component of the nervous system? Vagus nerve Sympathetic nervous system Oculomotor nerve Parasympathetic nervous system

Sympathetic nervous system Most of the skin's blood vessels are innervated by the sympathetic nervous system. The sweat glands are innervated by cholinergic fibers but controlled by the sympathetic nervous system. Likewise, the sympathetic nervous system controls the arrector pili (pilomotor) muscles that cause elevation of hairs on the skin (pilo- means hair). The parasympathetic nervous system is one of three divisions of the autonomic nervous system. Sometimes called the rest and digest system, the parasympathetic system conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles in the gastrointestinal tract. The vagus nerve (also known as the 10th cranial nerve) is a very long nerve that originates in the brain stem and extends down through the neck and into the chest and abdomen. It supplies innervation to the heart, major blood vessels, airways, lungs, esophagus, stomach, and intestines. The oculomotor nerve is the third of 12 pairs of cranial nerves in the brain. This nerve is responsible for eyeball and eyelid movement.

A biology class is discussing blood flow directions and the role of arteries and veins. The professor says, "The skin is the only place where there is a direct anastomosis between an artery and a vein." What is the purpose for this type of blood flow in the skin? Nutrient delivery Temperature regulation Assist in elimination of toxins from the air Higher need for direct oxygenation

Temperature Regulation The skin is richly supplied with arteriovenous anastomoses in which blood flows directly between an artery and a vein, bypassing the capillary circulation. These anastomoses are important for temperature regulation. They can open up, letting blood flow through the skin vessels when there is a need to dissipate body heat, and close off, conserving body heat if the environmental temperature is cold. It has nothing to do with nutrient supply, elimination of toxins, or higher oxygen supply.

What is the source of nutrition for the epidermis? Melanocytes Bullae The dermis Pigment membranes

The dermis The dermis is the connective tissue layer that separates the epidermis from the subcutaneous fat layer. It supports the epidermis and serves as its primary source of nutrition.

Lichenified skin is defined as being: Oozing, crusted vesiculated skin Depigmentation Thickened skin with exaggerated markings Chronically irritated, oily, scaly skin

The reticular dermis is a complex meshwork of three-dimensional collagen bundles interconnected with large elastic fibers and is the thicker area of the dermis, which forms the bulk of the dermal layer. The papillary layer of the dermis is a thin superficial layer that interdigitates directly with the epidermis. Lichenified skin is thickening and roughening of the skin or accentuated skin markings that may be secondary to repeated rubbing, irritation, or scratching.

Which skin disorder is likely to result from the localized lack of melanin production by melanocytes? Bullae Vitiligo Rash Melasma

Vitiligo In cases of vitiligo, depigmented areas may contain no melanocytes, greatly altered or decreased amounts of melanocytes, or, in some cases, melanocytes that no longer produce melanin. Melasma results from increased pigmentation. Neither bullae nor rashes are consequences of alteration in melanocyte function.

During a physical assessment, a nurse determines that a client has excessively dry skin. Which term would the nurse use to document this condition? Seborrhea Alopecia Xerosis Pruritus

Xerosis Dry skin, also called xerosis, may be a natural occurrence, as in the drying of skin associated with aging, or it may be symptomatic of an underlying systemic disease or skin disorder such as contact dermatitis or diabetes mellitus.

When trying to explain the advantages of using an emollient over other products to a client suffering from dry skin, the nurse will emphasize that emollients: provide moisture-proof material to the skin by providing a thick cream layer as a barrier. can replenish the oils on the skin surface because they contain fatty acids. will contain some form of numbing agent like lidocaine to help with the itching. will draw water out from the deeper skin layers.

can replenish the oils on the skin surface because they contain fatty acids. Emollients are lotions containing fatty acids that replenish the oils on the skin surface, but usually do not leave a residue on the skin. Humectants are the additives in lotions that draw out the water from the deeper skin layers and hold it on the skin surface. However, the water that is drawn to the skin is transepidermal water, not atmospheric water. Thus, continued evaporation from the skin can actually exacerbate dryness. Occlusives are thick creams that contain petroleum to act as a barrier. Lotions or cream additives include steroids or mild anesthetics, such as camphor, menthol, lidocaine, or benzocaine. These agents work by suppressing itching while moisturizing the skin.

A 42-year-old female client complains of extreme xerosis and states nothing seems to work for her skin. The most appropriate treatment would be to apply: exfoliation products to remove dry skin. emollients or occlusives, as they are the most effective treatment. urea lotion. alpha-hydroxy acids to help draw water to the surface.

emollients or occlusives, as they are the most effective treatment. Emollients and occlusives are thick creams or ointments that contain moisture-proof ingredients to prevent water loss from the skin. The other options will increase water loss.

The nurse notes a blister on a client's skin. Which description best defines this area? flat macular rash elevated petechiae fluid-filled papule raised lesion

fluid-filled papule A blister is a vesicle or fluid-filled papule. Petechiae are purplish red spot that appear on the skin as a result of intradermal or submucousal hemorrhage. A macular rash is composed of small, flat blemishes or discoloration that is flush with the skin surface. There are many types of raised lesions and this term does not accurately describe a blister.

The skin assessment of a black client reveals the presence of white areas on the skin that are flat, nonpalpable, less than 1 cm in diameter, and have a circumscribed border. How does the nurse document the finding? petechiae melasma macule erosion

macule A macule is a flat, nonpalpable skin color change that is brown, white, tan, purple, or red and less than 1 cm with a circumscribed border.

The health care provider has characterized a client's skin lesion as being a temporary eruption but has cautioned the client against repeated rubbing or scratching to avoid lichenization. What is the most likely categorization of the client's skin lesion? callus rash blister corn

rash A rash is a temporary eruption of the skin that can result in excoriation or lichenization if rubbed or scratched excessively. Corns, calluses, and blisters are not noted to share these characteristics.

n explaining a papule to a client, a nurse defines it as being a: closed, rounded space containing fluid. flat-topped, solid lesion. small abscess. small, raised solid mass with a circumscribed border.

small, raised solid mass with a circumscribed border. A papule is an elevated, palpable, solid mass with a circumscribed border less than 0.5 cm.

The skin is richly supplied with arteriovenous anastomoses in which blood flows directly between an artery and a vein, bypassing the capillary circulation. This particular vascular structure allows a client to: regulate body temperature. maximize skin perfusion. form "goose bumps" when cold. prevent localized hypoxia.

regulate body temperature. Anastomoses are important for temperature regulation. They can open up, letting blood flow through the skin vessels when there is a need to dissipate body heat, or close off, conserving body heat if the environmental temperature is cold. Although goose bumps are a reaction to cold, they are actually caused by the contraction of the arrector pili muscles. They are not involved specifically in oxygenation.