Chapter 5 Integumentary System Adaptive Test

If a large number of whiteheads appear on the skin of the forehead, which of the following would result? -fine hairs on the forehead would become brittle - the forehead's skin would become dry - bacteria on the forehead's skin would grow and multiply freely - all of the above

All of the above When sebaceous glands are blocked, sebum cannot be excreted onto the skin. Sebum functions to soften/lubricate the hair and skin, and it acts as a bactericidal agent.

Which skin function is NOT correctly matched with the structure that accounts for that function? -keratinocytes: physical barrier -tactile corpuscles: cutaneous sensation -apocrine gland: thermoregulation -eccrine glands: excretion

Apocrine gland: thermoregulation While the function of the apocrine cells is not well understood, they do not provide much assistance in thermoregulation because of their location.

Which of the following is NOT an immediate threat to the system as a result of burns? - dehydration - renal failure - electrolyte imbalance - bacterial infection

Bacterial infection. While it is true that infection is a long term threat, the fluid balance must be restored first in order to stabilize the burn trauma.

Which of the following would NOT be a correct characteristic of melanoma? - asymmetry - diameter of 12 mm - border regularity - color that is dark black or brown

Border regularity Border irregularity would be a sign of melanoma, especially if you were to see rough or notched edges.

D. stratum basale Cells migrate upwards through the epidermis after being generated by mitosis in the stratum basale.

Cell division would be most common among cells in which of the labeled layers?

New portions of a nail are produced at the nail bed. Is this statement true or false?

False New nail is produced at the nail matrix.

In the presence of sunlight, Vitamin D precursors are produced. This is important for the transport of sodium in our intestines. Is this statement true or false?

False. It is true that the vitamin D precursors are produced in the skin as cholesterol is converted into cholecalciferol when you are exposed to UV light. However, vitamin D is crucial for calcium transport, not sodium, in the gut.

In people with lighter skin, respiratory failure can lead to a change in the color of the skin. Which pigmentation factor is affecting this change? -carotene -folic acid -hemoglobin -melanin

Hemoglobin As the blood becomes hypoxic, hemoglobin is carrying less oxygen. This deoxygenated state leads to the condition known as cyanosis.

What is the most common cell type in the epidermis? -dendritic cells -fibroblasts -keratinocytes -macrophages

Keratinocytes Keratinocytes are the primary cells that form the stratified layers of the epidermis.

areolar connective tissue The loose connective tissue within the papillary layer of the dermis is rich in blood vessels and cells that function in the body's defenses.

Layer B is composed primarily of __________. -simple squamous epithelium -areolar connective tissue -dense irregular connective tissue -dense regular connective tissue

In general, skin cancer is least likely to develop in which of the following locations? -scalp -forehead -nose -the back of the hand

Scalp The skin of scalp has hair, which gives it added protection from the damaging ultraviolet rays of the sun.

Susan sat out in the sun watching a baseball game. She developed small blisters on her unprotected shoulders and neck. What type of burn is represented by the formation of the blisters? -first-degree burn -second-degree burn -third-degree burn -full-thickness burn

Second-degree burn Second-degree burns injure the epidermis and the superficial region of the dermis. Symptoms mimic those of first-degree burns, but blisters also appear.

Which stratum of the epidermis contains the stem cells responsible for regenerating the more superficial layers? -stratum granulosum -stratum spinosum -stratum corneum -stratum basale

Stratum basale The stratum basale is the deepest layer of the epidermis and consists of one layer of actively mitotic stem cells. The stem cells in this layer generate the cells that will migrate to the more superficial layers: spinosum, granulosum, and corneum.

Which dermal layer is responsible for the dermal properties of skin that are evident as cleavage lines? -the papillary layer -the reticular layer -the basal layer -the granular layer

The reticular layer The dermis has a collection of dense regular connective tissues with large amounts of collagen arranged in a regular pattern that creates cleavage lines.

If a person were born without eccrine glands, what skin function would he or she have a hard time completing? -metabolic function -thermoregulation -cutaneous sensation -having the skin act as a physical barrier

Thermoregulation Sweat is used for thermoregulation. As sweat is released onto the surface of the epidermis, heat from the body is conducted into the water. Water is a better conductor of heat than air is. As the sweat evaporates, the heat from the body dissipates into the environment.

Detection of pressure stimulus Structure B is a lamellar (Pacinian) corpuscle that responds to cutaneous contacts involving deep pressure.

What is the function of structure B? -secretion of sweat -production of defensive chemicals -detection of pressure stimulus -storage of fat

To lubricate hair and prevent infection. Structure A produces sebum, an oily secretion that coats the hairs and prevents infectious agents from penetrating the hair shaft.

What is the function of the secretion from A? -to lubricate hair and prevent infection -to waterproof the epidermis -to cool the body -to provide nourishment for the cells in the hair

dermal papilla Dermal papillae are projections of the dermis that form indentations in the overlying epidermis.

What is the structure indicated by label E? - the hypodermis - the stratum corneum - a dermal papilla - a hair root

Layer C consists primarily of dense, interwoven fibers of collagen designed to resist tearing from any direction.

Which layer is composed primarily of dense irregular connective tissue?

Structures A, B, C, and D are located in the dermis. Each of the labeled structures is located within the dermal layer of the skin.

Which of the following correctly describes a common feature of all structures labeled A through D in the figure? -Structures A, B, C, and D are located in the dermis. -Structures A, B, C, and D are composed primarily of smooth muscle. -Structures A, B, C, and D are all various types of glands. -All the listed statements correctly describe structures A, B, C, and D.

Subcutaneous. The hypodermis ("under the skin") layer is also referred to as the subcutaneous region.

Which of the following terms describes layer D? -subcutaneous -epidermal -reticular -papillary

A. Stratum corneum Cell of this layer are dead and do not participate in mitosis.

Which of these epidermal layers would be LEAST likely to develop cancer?

A; holocrine The gland at A secretes an oily material rich in lipids but does not do it through the use of vesicles and exocytosis.

Which of these glands is properly matched with its mode of secretion? A; holocrine A; merocrine C; apocrine C; holocrine

Melanocyte. Melanocytes within the stratum basale produce the pigment melanin, which is deposited within the deeper layers of the epidermis.

Which skin-color-associated, pigment-producing cell is located in the labeled layer D?

The skin is permeable to organic solvents, such as acetone or turpentine, because they ________. -can dissolve the lipid bilayers of epidermal and dermal cell plasma membranes -are small molecules that bypass skin cells and therefore directly enter the blood -solubilize the skin's keratin filaments -solubilize the skin's collagen fibers

can dissolve the lipid bilayers of epidermal and dermal cell plasma membranes Organic solvents are carbon-based substances that are capable of dissolving or dispersing one or more other substances like the phospholipids of the plasma membrane.

You discover a new type of gland associated with the skin. Chemical analysis of the product shows a secretion has a pH of 4, consists of 99% water, and contains traces of normal electrolytes including urea, vitamin C, and dermicidin. There are no traces of fats or proteins. How would you classify this new gland? -ceruminous gland -mammary gland -eccrine gland -sebaceous gland

eccrine gland Eccrine glands produce true sweat, which was described in this scenario.

Which skin pigment is made in the skin as a natural defense against UV radiation? -melanin -hemoglobin -carotene -keratin

melanin Melanin is the only one of the three pigments (melanin, carotene, and hemoglobin) that contribute to skin color that is actually produced in the skin itself.

Which of the following is a metabolic function of skin? -synthesis of a vitamin D precursor -elimination of nitrogenous wastes -body temperature regulation -cutaneous sensation

synthesis of a vitamin D precursor Yes, this is a function of the skin carried out by chemical reactions in the skin. When sunlight bombards the skin, modified cholesterol molecules are converted to a vitamin D precursor (called cholecalciferol), which is transported via the blood to the liver and kidneys, where it is converted into a hormone called calcitriol, or active vitamin D.

The source of the fluid that accumulates in a blister is________. -water that is absorbed from the environment into the skin -water that is squeezed out of the overlying epidermal cells -the plasma of the blood flowing through the numerous dermal blood vessels -none of the above

the plasma of the blood flowing through the numerous dermal blood vessels The epidermis is avascular but highly innervated; the underlying dermis lacks the number of nerve endings but is rich in blood vessels.