Chapter 5
49) The function of the root hair plexus is to ________. A) serve as a source for new epidermal cells for hair growth after the resting stage has passed B) bind the hair root to the dermis C) allow the hair to assist in touch sensation D) cause apocrine gland secretion into the hair follicle
) allow the hair to assist in touch sensation
Joe just burned himself on a hot pot. and the burn is quite painful. Joeʹs burn would best be 29) described as a _______ burn.
1st degree
Robert, a surfer, has a mole that has changed its shape and size. His doctor, applying the ABCDE) rule, diagnosed a melanoma. What do the letters ABCDE) represent?
A = asymmetry B = border irregularity C = color D = diameter E = elevation
Betty, an 83 year old woman, is bedfast due to a severely broken hip. Unfortunately, she has developed a decubitus ulcer. What is a decubitus ulcer and what may have caused it to occur?
A decubitus ulcer is a localized breakdown and ulceration of skin due to interference with its blood supply. Usually occurs over a bony prominence, such as the hip or heel, that is subjected to continuous pressure; also called a bedsore.
Water loss through the epidermis could cause a serious threat to health and well-being. Which of the following protects us against excessive water loss through the skin? A) Glycolipids that are secreted by keratinocytes into extracellular spaces. B) Fat associated with skin prevents water loss. C) The dermis is the thickest portion of the skin and water cannot pass through it. D) The size and shape of the cells that make up the stratum spinosum, as well as the thick bundles of intermediate filaments.
A) Glycolipids that are secreted by keratinocytes into extracellular spaces.
In addition to protection (physical and chemical barrier), the skin serves other functions. Which of the following is another vital function of the skin? A) It converts modified epidermal cholesterol to a vitamin D precursor important to calcium metabolism. B) It aids in the transport of materials throughout the body. C) It absorbs vitamin C so that the skin will not be subject to diseases. D) The cells of the epidermis store glucose as glycogen for energy.
A) It converts modified epidermal cholesterol to a vitamin D precursor important to calcium metabolism.
Which of the following statements indicates the way in which the bodyʹs natural defenses protect 61) the skin from the effects of UV damage? A) Prolonged exposure to the sun induces melanin dispersion, which in turn acts as a natural sunscreen. B) Carotene, which accumulates in the stratum corneum and hypodermal adipose tissue, is synthesized in large amounts in the presence of sunlight. C) The skin is protected by increasing the number of epidermal dendritic cells, which help to activate the immune system. D) The skin is protected by the synthesis of three pigments that contribute to the skinʹs color.
A) Prolonged exposure to the sun induces melanin dispersion, which in turn acts as a natural sunscreen.
Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? A) Thickening of epidermis to form a callus in places where the skin is exposed to friction. B) Formation of cerumen wax to deter insects from entering the ear. C) Changes in the response of the hair follicle to dihydrotestosterone (DHT). D) Production of vitamin D initiated by the suns UV light striking the skin.
A) Thickening of epidermis to form a callus in places where the skin is exposed to friction.
The dermis is a strong, flexible connective tissue layer. Which of the following cell types are likely to be found in the dermis? A) fibroblasts, macrophages, and mast cells B) goblet cells, parietal cells, and chondrocytes C) monocytes, reticulocytes, and osteocytes D) osteoblasts, osteoclasts, and epithelial cells
A) fibroblasts, macrophages, and mast cells
The epidermis consists of five layers of cells, each layer with a distinct role to play in the health, well-being, and functioning of the skin. Which of the following layers is responsible for cell division and replacement? A) stratum basale B) stratum lucidum C) stratum granulosum D) stratum corneum
A) stratum basale
William has a cut that is superficial, painful but not bleeding. Based on this information you would predict that the cut has penetrated to ________. A) the stratum basale but not the dermal layers B) the papillary layer but not the reticular layer C) the subcutaneous layer, but no deeper D) the stratum corneum but not the stratum granulosum
A) the stratum basale but not the dermal layers
A summertime golden bronze tan may not be a tan at all; especially if the skin appears almost metallic bronze, it may be the result of ________ disease.
Addisonʹs
Appearance of a permanent tan; bronzing.
Addisonʹs disease
All of the following will help the skin to fight infection but one. Which of the following will have little effect on the skinʹs ability to fight infection? A) Increased secretions of defensins from skin cells. B) Greater production of melanin. C) More tight junctions between keratinocytes of the stratum corneum. D) Greater production of keratinocytes resulting in more layers of the stratum corneum.
B) Greater production of melanin.
85) The surge of sex hormones that accompanies puberty has a wide range of effects on the body. One of those effects is to enhance the activity of the sebaceous glands, increasing the production of sebum. Which of the following is the most likely to result from the increased sebaceous activity? A) Increased cooling of the skin. B) Increased oily appearance and more acne. C) Decreased vitamin D synthesis. D) Increased hair growth.
B) Increased oily appearance and more acne.
Select the most correct statement concerning skin cancer. A) Squamous cell carcinomas arise from the stratum corneum. B) Melanomas are rare but must be removed quickly to prevent them from metastasizing C) Most tumors that arise on the skin are malignant. D) Basal cell carcinomas are the least common but most malignant.
B) Melanomas are rare but must be removed quickly to prevent them from metastasizing
Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? A) Lack of pain in third degree burns due to damage to sensory nerves in the dermis. B) Release of sweat by eccrine glands in response to heat. C) An increase in sebum production in response to androgens (male sex hormones). D) Excretion of salts within the sweat.
B) Release of sweat by eccrine glands in response to heat.
The papillary layer of the dermis is composed of loosely packed connective tissue with numerous 59) peg-like projections that provide a great deal of surface area connecting the dermis to the epidermis. Which of the statements below do not represent benefits provided by the papillary layerʹs anatomy? A) The high surface area allows for a stronger connection of dermis to epidermis. B) The looseness allows for easy separation of the dead cell layer of epidermis to be shed. C) The looseness allows for phagocytes to roam through the tissue and search for infection. D) The spaces in the connective tissue allow many small blood vessels to deliver nutrients and pickup waste diffusing from the superficial epidermal layers.
B) The looseness allows for easy separation of the dead cell layer of epidermis to be shed.
Melanocytes and keratinocytes work together in protecting the skin from UV damage when keratinocytes ________. A) maintain the appropriate pH in order for the melanocyte to synthesize melanin granules B) accumulate the melanin granules on their superficial portion, forming a UV-blocking pigment layer C) maintain the appropriate temperature so the product of the melanocyte will not denature D) provide the melanocyte with nutrients necessary for melanin synthesis
B) accumulate the melanin granules on their superficial portion, forming a UV-blocking pigment layer
Which glands produce ear wax? A) merocrine glands B) ceruminous glands C) apocrine glands D) eccrine glands
B) ceruminous glands
The major regions of a hair shaft include all of the following except ________. A) medulla B) external root sheath C) cuticle D) cortex
B) external root sheath
Cells of the stratum spinosum have many interlocking desmosomes that will remain between the cells as they migrate to the stratum corneum. These cell junctions serve the body by ________. A) stopping water loss and preventing dehydration B) preventing mechanical stress or trauma from damaging the epidermis C) preventing ultraviolet light from penetrating the deeper layers of the epidermis D) allowing secretions like sweat or sebum to pass through
B) preventing mechanical stress or trauma from damaging the epidermis
Which layer of the epidermis will be supplied with the highest levels of oxygen from the blood? A) stratum corneum B) stratum basale C) stratum granulosum D) stratum spinosum
B) stratum basale
Which layer of skin is LEAST protected by melanin? A) stratum basale b) stratum corneum c) stratum granulosum D) stratum sponosum
B) stratum corneum
Which of the following is a skin sensory receptor for touch? A) Pacinian corpuscle B) tactile corpuscle C) free nerve ending D) Ruffini body
B) tactile corpuscle
How are burns commonly classified? Give an example.
Burns are classified according to their severity or depth. For example, in first-degree burns, only the epidermis is damaged; in second degree burns, the epidermis and upper dermis are damaged; in third degree burns, there is widespread damage of epidermis and dermis.
The friction ridges seen in finger, palm and foot prints are different among various people but very 60) similar between identical twins. This evidence suggests which of the following? A) That friction ridges allow for better tactile sensation. B) That friction ridges change over time. C) That friction ridges are genetically determined. D) That friction ridges aid in griping.
C) That friction ridges are genetically determined.
The arrector pili muscleʹs predominate, useful function in humans is to ________. A) provide warmth by making the hair stand on end B) preventing germs from entering the hair shaft C) assisting in the release sebum from nearby sebaceous glands D) stimulating faster hair growth
C) assisting in the release sebum from nearby sebaceous glands
A splinter penetrated into the skin of the sole of the foot, almost to the papillary region of the dermis. Which layer of the epidermis would be the final layer injured? A) granulosum B) lucidum C) basale D) spinosum
C) basale
Burns are devastating and debilitating because of loss of fluids and electrolytes from the body. How do physicians estimate the extent of burn damage associated with such dangerous fluid loss? A) by measuring urinary output and fluid intake B) through blood analysis C) by using the ʺrule of ninesʺ D) by observing the tissues that are usually moist
C) by using the ʺrule of ninesʺ
Sudoriferous (sweat) glands are categorized as two distinct types. Which of the following are the two types of sweat glands? A) holocrine and mammary B) mammary and ceruminous C) eccrine and apocrine D) sebaceous and merocrine
C) eccrine and apocrine
A patient has skin that is slightly blue in color. A likely treatment for this person might be ________. A) increasing fluids through IV therapy B) encouraging the patient to eat more orange colored vegetables (rich in beta carotene) C) giving the patient supplemental oxygen by mask D) exposing the patient to more sunlight.
C) giving the patient supplemental oxygen by mask
63) What are the most important factors influencing hair growth? A) sex and hormones B) the size and number of hair follicles C) nutrition and hormones D) age and glandular products
C) nutrition and hormones
A light skinned person may appear pink when they become over heated. The best explanation for this is ________. A) the heart is pumping faster because the person was probably exercising B) blood flow has increased to the sweat glands in order to increased their metabolic activity C) the blood vessels of the dermis have undergone vasodilation, bringing a greater volume of blood to the skin D) the melanocytes are responding to the heat of the sun and change the appearance of the skin with increased production
C) the blood vessels of the dermis have undergone vasodilation, bringing a greater volume of blood to the skin
The dermis has two major layers. Which layer constitutes 80% of the dermis and is responsible for the tension lines in the skin? A) the subcutaneous layer B) the hypodermal layer C) the reticular layer D) the papillary layer
C) the reticular layer
Cell remnants of the stratum corneum.
Cornified keratinocytes
The composition of the secretions of the eccrine glands is ________. A) fatty substances, proteins, antibodies, and trace amounts of minerals and vitamins B) metabolic wastes C) primarily uric acid D) 99% water, sodium chloride, trace amounts of wastes, and vitamin C
D) 99% water, sodium chloride, trace amounts of wastes, and vitamin C
Which statement correctly explains why hair appears the way it does? A) Gray hair is the result of hormonal action altering the chemical composition of melanin. B) Air bubbles in the hair shaft cause straight hair. C) Perfectly round hair shafts result in wavy hair. D) Kinky hair has flat, ribbonlike hair shafts.
D) Kinky hair has flat, ribbonlike hair shafts.
Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? A) Removal of nitrogenous compounds like urea within the sweat. B) The secretion of antibacterial compounds in sebum. C) The near waterproof secretions of glycolipids that is released by cells in the stratum granulosum. D) Release of chemical signals by keratinocytes that have been damaged by UV light that will increase the production of melanin.
D) Release of chemical signals by keratinocytes that have been damaged by UV light that will increase the production of melanin. Answer: D
Despite its apparent durability, the dermis is subject to tearing. How might a person know that the dermis has been previously stretched and/or torn? A) There is an episode of acute pain due to the large number of tactile corpuscles. B) The stretching causes the tension lines to disappear. C) The blood vessels in the dermis rupture and the blood passes through the tissue, causing permanent ʺblack-and-blue marks.ʺ D) The appearance of visible, silvery-white scars is an indication of stretching of the dermis.
D) The appearance of visible, silvery-white scars is an indication of stretching of the dermis.
A light skinned person who is very cold may have a pale appearance. Which of the following is the best explanation for why this might be so? A) The cold has slowed the movement of blood. B) The person is in fear of hypothermia (sever cold exposure). C) The personʹs blood vessels in the epidermis have undergone vasodilation (widening). D) The personʹs blood vessels in the dermis have undergone vasoconstriction (narrowing).
D) The personʹs blood vessels in the dermis have undergone vasoconstriction (narrowing).
Changes in the color of skin are often an indication of a homeostatic imbalance. Which of the 62) following changes would suggest that a patient is suffering from Addisonʹs disease? A) Black-and-blue marks become evident for no apparent cause. B) It is impossible to suggest Addisonʹs disease from an inspection of a personʹs skin. C) The skin appears to have an abnormal, yellowish tint. D) The skin takes on a bronze or metallic appearance.
D) The skin takes on a bronze or metallic appearance.
The sebaceous glands are simple alveolar glands that secrete a substance known as sebum. The secretion of sebum is stimulated ________. A) by high temperatures B) when the air temperature drops C) as a protective coating when one is swimming D) by hormones, especially androgens
D) by hormones, especially androgens
Which of the following cells and their functions are correctly matched? A) tactile cells - protection B) melanocytes -protects cells in the stratum corneum from damaging effects of sunʹs rays C) keratinocytes -provide sense of touch and pressure D) dendritic cells -activate the immune system
D) dendritic cells -activate the immune system
Eyebrow hairs are always shorter than hairs on your head because ________. A) the vascular supply of the eyebrow follicle is one-tenth that of the head hair follicle B) they grow much slower C) hormones in the eyebrow follicle switch the growth off after it has reached a predetermined length D) eyebrow follicles are only active for a few months
D) eyebrow follicles are only active for a few months
A surgeon opens her patient by cutting the integument parallel to the cleavage lines of the dermis (tension lines). This will result in ________. A) greater chance of infection B) less chance for infection C) slowed healing and grater scaring D) faster healing of the skin and less scaring
D) faster healing of the skin and less scaring
Apocrine glands, which begin to function at puberty under hormonal influence, seem to play little role in thermoregulation. Where would we find these glands in the human body? A) beneath the flexure lines in the body B) in the palms of the hands and soles of the feet C) in all body regions and buried deep in the dermis D) in the axillary and anogenital area
D) in the axillary and anogenital area
The single most important risk for skin cancer is ________. A) race B) use of farm chemicals C) genetics D) overexposure to UV radiation
D) overexposure to UV radiation
The reason the hypodermis acts as a shock absorber is that ________. A) the cells that make up the hypodermis secrete a protective mucus B) it is located just below the epidermis and protects the dermis from shock C) it has no delicate nerve endings and can therefore absorb more shock D) the major part of its makeup is adipose, which serves as an effective shock absorber
D) the major part of its makeup is adipose, which serves as an effective shock absorber
Skin macrophages that help activate the immune system.
Dendritic cells
May indicate embarrassment, fever, hypertension, inflammation, or allergy.
Erythema
Why is profuse sweating on a hot day good, and yet a potential problem?
Good because the sweat and evaporating of the sweat causes cooling of the body. Bad because excessive water and salt loss may occur. Fluid and electrolyte imbalances may follow.
Balding men have tried all kinds of remedies, including hair transplants, to restore their lost locks. Explain the cause of male pattern baldness.
It appears to be genetically determined and sex-linked, and is possibly caused by a delayed-action gene that responds to DHT and alters normal metabolism.
Usually indicates a liver disorder.
Jaundice
The protein found in the epidermis that is responsible for toughening the skin.
Keratin
In addition to the synthesis of vitamin D, keratinocytes are able to carry out some other biologically important functions. Name at least two of these other functions.
Keratinocyte enzymes can neutralize carcinogens that penetrate the epidermis. Keratinocytes are also able to convert topical cortisone to a more active anti-inflammatory form.
Melanoma is a form of skin cancer that arises from melanocytes. Melanoma is most common in Caucasians between 40 and 70 years of age. Explain why Caucasians would have a greater incidence of melanoma.
Melanoma has its beginnings in melanocytes, the skin pigment cells. These cells produce the dark protective pigment called melanin to protect against sun damage to DNA. Since the melanocytes in Caucasian people do not make as much melanin per cell as darker-skinned individuals, their melanocytes are more easily sun-damaged, resulting in damaged DNA cells that are more apt to lose genetic control of their own cell division.
Cells plus a disc-like sensory nerve ending that functions as a sensory receptor for touch.
Merkel disc
May indicate fear, anger, anemia, or low blood pressure.
Pallor
The layer that contains the mitotic viable cells of the epidermis.
Stratum basale
The layer of the epidermis where the cells are considered protective but nonviable.
Stratum corneum
There are several reasons other than genetics for hair loss. Identify some of these other factors.
Stressors such as acutely high fever, surgery, severe emotional trauma; drugs such as antidepressants and chemotherapy drugs; burns and radiation; lack of adequate nutrition due to poor skin circulation; and a protein-deficient diet can cause hair loss or thinning.
The glands that serve an important function in thermoregulation.
Sudoriferous glands
Billions of consumer dollars are spent for deodorants and antiperspirants each year. Explain the production of body odors frequently associated with axillary skin.
Sweat is mostly an odorless watery secretion produced by eccrine and apocrine glands. The odor usually arises when bacteria break down lipids and proteins in the surface secretions.
The 68-year-old patient was admitted to the hospital medical floor with a diagnosis of chronic bronchitis. His wife asks the nurse why his skin looks blue. How would you explain cyanosis to the patient and his wife?
The 68-year-old patient was admitted to the hospital medical floor with a diagnosis of chronic bronchitis. His wife asks the nurse why his skin looks blue. How would you explain cyanosis to the patient and his wife?
Mary noticed a large, brown spot on her skin. She has been playing tennis in the sun for several years without sun protection. She reported the discovery to a friend, who told her to apply the ABCD rule to determine whether or not she had malignant melanoma. Her friend told her that if her answer was ʺnoʺ to the questions that were asked by the ABCD rule, she had nothing to worry about. What is the ABCD rule and should she ignore the spot if her answers are negative?
The ABCD rule refers to the following: asymmetrywhere the two sides of the spot do not match; border irregularitythe borders are not round and smooth; colorthe pigmented spot contains shades of black, brown, tan, and sometimes blues and reds; and diameter the spot is larger than 6 mm in diameter. It is imperative that Mary have a physician examine the spot immediately. Any unusual lesion on the skin of a sun worshipper should be examined and the ABCD rule does not account for all possible factors, such as rapid growth, even if less than 6 mm.
The skin protects, but how does it protect us and from what? Describe how the epidermal dendritic cells and melanocytes protect us. Describe what these cells protect us from.
The epidermal dendritic cells act as antigen presenting cells (APC), they present part of the pathogens (fragments of pathogens called epitopes) to other immune system cells to trigger an immune response to an infection. The melanocytes produce melanin in response to exposure to cell damaging, ultraviolet light. UV light is converted to heat when it strikes melanin pigment. Unlike UV light, heat will not damage the cells particularly the DNA within the nucleus of the skinʹs cells.
Explain why soap that has an alkaline base may not be healthy for some patients to use daily.
The skinʹs acid mantle retards growth of bacteria. Soap may destroy the acid mantle of the skin, causing it to lose its protective mechanism. Some soaps contain antibacterial agents, which can change the natural flora of the skin.
The temperature yesterday was an uncomfortable 98°F. You unwisely chose to play tennis at noon, counting on your bodyʹs internal defenses to protect you against heat exhaustion. How did your body respond to this distress?
The thermoreceptors sense the temperature change, and neural stimulation responds by stimulating sweat glands. Their watery products evaporated at the skin surface and cooled the body. Blood vessels in the dermis also responded by dilating and releasing heat to the exterior.
Why are the apocrine sweat glands fairly unimportant in thermal regulation?
They are largely confined to the axillary and anogenital regions rather than distributed on the body where heat can be more readily dissipated.
Hair that lacks pigment and is often called ʺimmature hair.ʺ
Vellus
Which of the following is not one of the functions of the skin? A) Gives the body its overall shape, loss of this function can be seen with the drooping of skin with age. B) Conducts endergonic metabolic chemical reactions using the suns energy to initiate vitamin D synthesis. C) Delivers important information about our environmental conditions to our brains. D) Holds a portion of the bloods total volume to be shunted (diverted) to other organs when needed.
a) Gives the body its overall shape, loss of this function can be seen with the drooping of skin with age.
The Waldorf family was caught in a fire but escaped. Unfortunately, the father and daughter suffered burns. The father had second-degree burns on his entire chest, abdomen, and both arms, and third -degree burns on his entire left lower extremity. The daughter suffered first-degree burns on her whole head and neck and second-degree burns throughout both lower extremities. a. What percentage of the fatherʹs body was covered by burns? b. What percentage of the daughterʹs body received first-degree burns? c. What part of the daughterʹs body has both the dermis and epidermis involved? d. The father experiences a good deal of pain in the area of the chest and abdomen, but little pain in the leg. Why?
a. 45% (18% anterior torso + 9% both arms but not forearms + 18% lower extremity) b. 9% c. 36% d. Normally, third-degree burns sear nerve endings off. When the tissue regenerates, pain will return. Second-degree burns are usually very painful because of the irritated but live nerve endings.
The ________ are the small muscles located in the dermis that cause goose bumps.
arrector pili
The action of the ____________ muscle is very similar in humans as it is in other mammals but its beneficial functions differ.
arrector pili
A bluish color in light-skinned individuals
cyanosis
The _______ contains blood vessels and nerve fibers while the epidermis does not.
dermis
The pinkish hue of individuals with fair skin is the result of the crimson color of oxygenated hemoglobin (contained in red blood cells) circulating in the dermal capillaries and reflecting through the _________.
epidermis
The layer of the epidermis immediately under the stratum lucidum in thick skin is the stratum ________.
granulosum
The most abundant cells of the epidermis.
keratinocytes
The only place you will find stratum ________ is in the skin that covers the palms, fingertips, and soles of the feet.
lucidum
The white crescent portion of the nail is called the ________.
lunula
Pigment-producing cells in the epidermis are ________.
melanocytes
Regardless of race, all human beings have about the same number of ________.
melanocytes
The skin cancer most likely to metastasize is cancer of the ____________.
melanocytes.
What are vellus hairs?
pale, fine body hair associated with newborn children, women, and bald men
During the __________ of hair growth, the matrix is inactive and the follicle atrophies.
regressive phase
The dense fibrous connective tissue portion of the skin is located in the ___________________.
reticular region of the dermis.
Cradle cap in infants is called ________.
seborrhea
Burns that result in injury to the epidermis and the upper regions of the dermis is called a ________ burn.
second-degree
For a doctor, simply looking at a patientʹs ______ can help in making a diagnosis.
skin
The coarse hair of the eyebrows and scalp is called ________ hair.
terminal
The apocrine sweat glands are not the primary gland involved in ___________.
thermoregulation.
What is the function of skin dermal folds and deep skin creases?
to accommodate for joint movement
