Ch. 5

The skin is not able to receive stimuli because the cells of the epidermis are not living and therefore there are no sensory receptors in the skin. True False

The dermis contains blood vessels and nerve fibers while the epidermis does not. True False

The reason the hypodermis acts as a shock absorber is that ________. it is located just below the epidermis and protects the dermis from shock. the cells that make up the hypodermis secrete a protective mucus. the major part of its makeup is adipose, which serves as an effective shock absorber. it has no delicate nerve endings and can therefore absorb more shock.

The protein found in large amounts in the superficial layer of epidermal cells is keratin. True False

Regardless of race, all human beings have about the same number of melanocytes. True False

Cells in the stratum corneum undergo mitosis to keep the layer thick and protective. True False

Thick skin has a more extensive dermal layer than thin skin. True False

A needle would pierce the epidermal layers of the forearm in which order? granulosum, basale, spinosum, corneum basale, spinosum, granulosum, lucidum, corneum corneum, granulosum, spinosum, basale basale, spinosum, granulosum, corneum

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? basale granulosum lucidum spinosum

Which of the following is a skin sensory receptor for touch? Ruffini body Pacinian corpuscle free nerve ending tactile cells

Which of the following cells and their function are correctly matched? keratinocytes - provide sense of touch and pressure dendritic cells - activate the immune system tactile cells - protection melanocytes - protects cells in the stratum corneum from damaging effects of sun's rays

Melanocytes and keratinocytes work together in protecting the skin from UV damage when keratinocytes ________. maintain the appropriate temperature so the product of the melanocyte will not denature. provide the melanocyte with nutrients necessary for melanin synthesis. maintain the appropriate pH in order for the melanocyte to synthesize melanin granules. accumulate the melanin granules on their superficial portion, forming a UV-blocking pigment layer.

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? stratum granulosum stratum basale stratum lucidum stratum corneum

Which of the following statements indicates the way in which the body's natural defenses protect the skin from the effects of UV damage? Carotene, which accumulates in the stratum corneum and hypodermal adipose tissue, is synthesized in large amounts in the presence of sunlight. Prolonged exposure to the sun induces melanin dispersion, which in turn acts as a natural sunscreen. The skin is protected by the synthesis of three pigments that contribute to the skin's color. The skin is protected by increasing the number of epidermal dendritic cells, which help to activate the immune system.

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? Glycolipids that are secreted by keratinocytes into extracellular spaces. The size and shape of the cells that make up the stratum spinosum, as well as the thick bundles of intermediate filaments. Fat associated with skin prevents water loss. The dermis is the thickest portion of the skin and water cannot pass through it.

A dendritic or Langerhans cell is a specialized ________. phagocytic cell squamous epithelial cell nerve cell melanocyte

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 ________. stopping water loss and preventing dehydration preventing mechanical stress or trauma from damaging the epidermis allowing secretions like sweat or sebum to pass through preventing ultraviolet light from penetrating the deeper layers of the epidermis

Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? Thickening of epidermis to form a callus in places where the skin is exposed to friction. Formation of cerumen wax to deter insects from entering the ear. Production of vitamin D initiated by the suns UV light striking the skin. Changes in the response of the hair follicle to dihydrotestosterone (DHT).

Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? The near waterproof secretions of glycolipids that is released by cells in the stratum granulosum. The secretion of antibacterial compounds in sebum. Removal of nitrogenous compounds like urea within the sweat. Release of chemical signals by keratinocytes that have been damaged by UV light that will increase the production of melanin.

Which layer of the epidermis will be supplied with the highest levels of oxygen from the blood? stratum basale stratum spinosum stratum corneum stratum granulosum

William has a cut that is superficial, painful but not bleeding. Based on this information, you would predict that the cut has penetrated to ________. the subcutaneous layer, but no deeper the stratum basale but not the dermal layers the stratum corneum but not the stratum granulosum the papillary layer but not the reticular layer

The dense fibrous connective tissue portion of the skin is located in the reticular region of the dermis. True False

The dermis is a strong, flexible connective tissue layer. Which of the following cell types are likely to be found in the dermis? osteoblasts, osteoclasts, and epithelial cells monocytes, reticulocytes, and osteocytes fibroblasts, macrophages, and mast cells goblet cells, parietal cells, and chondrocytes

The dermis has two major layers. Which layer constitutes 80% of the dermis and is responsible for the tension lines in the skin? the reticular layer the subcutaneous layer the papillary layer the hypodermal layer

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? There is an episode of acute pain due to the large number of tactile corpuscles. The stretching causes the tension lines to disappear. The appearance of visible, silvery-white scars is an indication of stretching of the dermis. The blood vessels in the dermis rupture and the blood passes through the tissue, causing permanent "black-and-blue marks."

The papillary layer of the dermis is composed of loosely packed connective tissue with numerous 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 layer's anatomy? The spaces in the connective tissue allow many small blood vessels to deliver nutrients and pick up waste diffusing from the superficial epidermal layers. The high surface area allows for a stronger connection of dermis to epidermis. The looseness allows for easy separation of the dead cell layer of epidermis to be shed. The looseness allows for phagocytes to roam through the tissue and search for infection.

The friction ridges seen in finger, palm and foot prints are different among various people but very similar between identical twins. This evidence suggests which of the following? That friction ridges allow for better tactile sensation. That friction ridges are genetically determined. That friction ridges aid in griping. That friction ridges change over time.

A surgeon opens her patient by cutting the integument parallel to the cleavage lines of the dermis (tension lines). This will result in ________. slowed healing and greater scaring faster healing of the skin and less scaring less chance for infection greater chance of infection

For a doctor, simply looking at a patient's skin can help towards making a diagnosis. True False

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. True False

Changes in the color of skin are often an indication of a homeostatic imbalance. Which of the following would indicate a liver disease such as hepatitis resulting in elevated bilirubin? Black-and-blue marks become evident for no apparent cause. The skin and sclera of the eyes appears to have an abnormal, n a bronze yellowish tint. The skin takes oor metallic appearance. It is impossible to suggest Addison's disease from an inspection of a person's skin.

A patient has skin that is slightly blue in color. A likely treatment for this person might be ________. increasing fluids through IV therapy exposing the patient to more sunlight encouraging the patient to eat more orange colored vegetables (rich in beta carotene) giving the patient supplemental oxygen by mask

During the regressive phase of hair growth, the matrix is inactive and the follicle atrophies. True False

The action of the arrector pili muscle is very similar in humans as it is in other mammals but its beneficial functions differ. True False

The major regions of a hair shaft include all of the following EXCEPT ________. cortex cuticle external root sheath medulla

Which statement correctly explains why hair appears the way it does? Gray hair is the result of hormonal action altering the chemical composition of melanin. Perfectly round hair shafts result in wavy hair. Kinky hair has flat, ribbonlike hair shafts. Air bubbles in the hair shaft cause straight hair.

The function of the root hair plexus is to ________. cause apocrine gland secretion into the hair follicle bind the hair root to the dermis serve as a source for new epidermal cells for hair growth after the resting stage has passed allow the hair to assist in touch sensation

What are the most important factors influencing hair growth? age and glandular products sex and hormones nutrition and hormones the size and number of hair follicles

Eyebrow hairs are always shorter than hairs on your head because ________. eyebrow follicles are only active for a few months they grow much slower the vascular supply of the eyebrow follicle is one-tenth that of the head hair follicle hormones in the eyebrow follicle switch the growth off after it has reached a predetermined length

The arrector pili muscle's predominate, useful function in humans is to ________. assist in the release sebum from nearby sebaceous glands stimulate faster hair growth provide warmth by making the hair stand on end prevent germs from entering the hair shaft

The reason that the nail bed appears pink is the presence of a large number of melanocytes in the underlying dermis. True False

The eccrine sweat glands are not the primary gland involved in thermoregulation. True False

When an individual is exposed to extremely cold air the dermal blood vessels will dilate so that more blood will be brought closer to the outside surface of the skin. True False

Which of the following glands secrete sebum, an oily like substance? apocrine glands eccrine glands merocrine glands sebaceous glands

Sudoriferous (sweat) glands are categorized as two distinct types. Which of the following are the two types of sweat glands? sebaceous and merocrine eccrine and apocrine mammary and ceruminous holocrine and mammary

The composition of the secretions of the eccrine glands is ________. fatty substances, proteins, antibodies, and trace amounts of minerals and vitamins 99% water, sodium chloride, trace amounts of wastes, and vitamin C metabolic wastes primarily uric acid

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? in the axillary and anogenital area in the palms of the hands and soles of the feet in all body regions and buried deep in the dermis beneath the flexure lines in the body

The sebaceous glands are simple alveolar glands that secrete a substance known as sebum. The secretion of sebum is stimulated ________. as a protective coating when one is swimming by hormones, especially androgens when the air temperature drops by high temperatures

Which of the following examples listed below illustrates homeostasis maintained by a negative feedback? Release of sweat by eccrine glands in response to heat. Lack of pain in third-degree burns due to damage to sensory nerves in the dermis. Excretion of salts within the sweat. An increase in sebum production in response to androgens (male sex hormones).

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? Increased cooling of the skin. Decreased vitamin D synthesis. Increased oily appearance and more acne. Increased hair growth.

In addition to protection (physical and chemical barrier), the skin serves other functions. Which of the following is another vital function of the skin? The cells of the epidermis store glucose as glycogen for energy. It converts modified epidermal cholesterol to a vitamin D precursor important to calcium metabolism. It aids in the transport of materials throughout the body. It absorbs vitamin C so that the skin will not be subject to diseases.

Which of the following is NOT one of the functions of the skin? Holds a portion of the bloods total volume to be shunted (diverted) to other organs when needed. Delivers important information about our environmental conditions to our brains. Conducts endergonic metabolic chemical reactions using the suns energy to initiate vitamin D synthesis. Gives the body its overall shape, loss of this function can be seen with the drooping of skin with age.

All of the following will help the skin to fight infection but one. Which of the following will have little effect on the skin's ability to fight infection? Increased secretions of defensins from skin cells. Greater production of keratinocytes resulting in more layers of the stratum corneum. Greater production of melanin. More tight junctions between keratinocytes of the stratum corneum.

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? The person's blood vessels in the epidermis have undergone vasodilation (widening). The person's blood vessels in the dermis have undergone vasoconstriction (narrowing). The cold has slowed the movement of blood. The person is in fear of hypothermia (sever cold exposure).

A light-skinned person may appear pink when they become over heated. The best explanation for this is ________. the blood vessels of the dermis have undergone vasodilation, bringing a greater volume of blood to the skin blood flow has increased to the sweat glands in order to increase their metabolic activity the heart is pumping faster because the person was probably exercising the melanocytes are responding to the heat of the sun and change the appearance of the skin with increased production

Joe just burned himself on a hot pot, and the burn is quite painful. Joe's burn would best be described as a third-degree burn. True False

The skin cancer most likely to metastasize is cancer of the melanocytes. True False

When a patient is said to have "third-degree burns," this indicates that the patient has burns that cover approximately one-third or more of the body. True False

Select the most correct statement concerning skin cancer. Squamous cell carcinomas arise from the stratum corneum. Melanomas are rare but must be removed quickly to prevent them from metastasizing. Basal cell carcinomas are the least common but most malignant. Most tumors that arise on the skin are malignant.

The single most important risk for skin cancer is ________. overexposure to UV radiation genetics race use of farm chemicals

Which type of skin cancer is the most dangerous because it is highly metastatic and resistant to chemotherapy? melanoma squamous cell carcinoma adenoma basal cell carcinoma

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? by using the "rule of nines" by measuring urinary output and fluid intake by observing the tissues that are usually moist through blood analysis

Which layer of tissue is damaged in a first-degree burn? epidermis hypodermis dermis both the epidermis and dermis