Chapter 5 The Integumentary System Flashcards
The subcutaneous layer is also known as the
a) dermis.
b) epidermis.
c) stratum corneum.
d) stratum basale.
e) hypodermis.
e) hypodermis.
Keratinized stratified squamous epithelium composes the
a) epidermis.
b) dermis.
c) hypodermis.
d) subcutaneous layer.
e) superficial fascia.
a) epidermis.
Choose the following statements that describe keratin.
1. Keratin is a tough, fibrous protein.
2. Keratin is used for pigmenting skin.
3. Keratin helps protect the skin.
4. Keratin participates in immune responses.
5. Keratin protects the skin from UV light.
a) 1 and 3
b) 1, 3, 4, 5
c) 2, 4, 5
d) 1, 2, 3, 4, 5
e) 3 and 5
a) 1 and 3
Which pigment secreted by specialized cells in the skin is capable of absorbing ultraviolet
light?
a) Keratin
b) Melanin
c) Melatonin
d) Carotene
e) Hemoglobin
b) Melanin
In a skin infection, which cell will take up and process microbial antigens?
a) Intraepidermal macrophages (Langerhans cells)
b) Melanocytes
c) Tactile epithelial cells (Merkel cells)
d) Stem Cells
a) Intraepidermal macrophages (Langerhans cells)
This layer is attached to the basement membrane by hemidesmosomes and to other cells by
desmosomes.
a) Stratum basale
b) Stratum spinosum
c) Stratum granulosum
d) Stratum lucidum
e) Stratum corneum
a) Stratum basale
Apoptosis of cells occurs within the
a) stratum basale.
b) stratum spinosum.
c) stratum granulosum.
d) stratum lucidum.
e) stratum corneum
c) stratum granulosum.
The majority of the skin does not contain stratum lucidum.
2. Stratum lucidum is found in areas of high friction, such as the palms and soles.
3. Live keratinocytes are located in the stratum lucidum.
4. Friction will cause the stratum lucidum to form calluses.
d) 1 and 2
Tactile epithelial cells are located in the
a) stratum basale.
b) stratum spinosum.
c) stratum granulosum.
d) stratum lucidum.
e) stratum corneum.
a) stratum basale.
Put the events of keratinization in order.
A. Accumulate keratohyalin granules
B. Cells increase in size, some retain ability to divide
C. Cell membrane thickens. Cells imbedded in lipid matrix.
D. Cells within this layer proliferate
D. Cells within this layer proliferate
B. Cells increase in size, some retain ability to divide
A. Accumulate keratohyalin granules
C. Cell membrane thickens. Cells imbedded in lipid matrix.
) Dense irregular connective tissue will be found in the
a) hypodermis.
b) basement membrane.
c) epidermis.
d) dermis.
e) subcutaneous (subQ) layer.
d) dermis.
Describe how fingerprints are formed and what they are used for
Epidermal ridges develop during the third or fourth fetal month as the epidermis
conforms to the contours of the underlying dermal papillae of the papillary region. The ridges
increase the surface area of the epidermis and thus increase the grip of the hand or foot by
increasing friction. Because the ducts of sweat glands open on the tops of the epidermal ridges as
sweat pores, the sweat and ridges form fingerprints upon touching a smooth object. The
epidermal ridge pattern is genetically determined and is unique for each individual allowing
these patterns to be used to identify individuals.
Albinism is the inherited inability to produce
a) melanin.
b) carotene.
c) both melanin and carotene.
d) keratin.
e) melanocytes.
a) melanin.
Which of the following are characteristics of thick skin? Select all that apply.
a) Found in the palms, soles of the feet and fingertips.
b) Does not contain hair follicles.
c) Contains more sweat glands than thin skin.
d) Contain epidermal ridges.
e) Lacking stratum lucidum.
f) Contains fewer corpuscles of touch than thin skin.
g) Stratum corneum has fewer layers in thick than thin.
a) Found in the palms, soles of the feet and fingertips.
b) Does not contain hair follicles.
c) Contains more sweat glands than thin skin.
d) Contain epidermal ridges.
Which structure found in the skin plays an important role in thermoregulation?
a) Melanocytes
b) Sebaceous glands
c) Sweat glands
d) Stratum lucidum
e) Epidermal ridges
c) Sweat glands
Which of the following structures found in the skin help prevent water loss and inhibit
bacterial growth on the surface of the skin? Select all that apply.
a) Arrector pili
b) Epidermal ridges
c) Sweat glands
d) Eponychium
e) Oil glands
f) Lamellar granules
e) Oil glands
f) Lamellar granules
Describe the structure and function of arrector pili.
Arrector pili are smooth muscles that extend from the superficial dermis of the skin to
the dermal root sheath around the side of the hair follicle. In its normal position, hair emerges at
an angle to the surface of the skin. Under physiological or emotional stress, such as cold or
fright, autonomic nerve endings stimulate the arrector pili muscle to contract, which pulls the
hair shafts perpendicular to the skin surface. This action causes “goose bumps” because the skin
around the shaft forms slight elevations.
Anorexia may cause adults to develop fine, unpigmented hairs to help with warmth and
insulation. Which type of hair is described?
a) Terminal
b) Vellus
c) Lanugo
d) Papilla
c) Lanugo
This type of exocrine gland undergoes a higher rate of mitosis due to its holocrine secretion.
a) Sebaceous gland
b) Eccrine gland
c) Apocrine gland
a) Sebaceous gland
Secretion mixture of fats, sterols, proteins and salts, that prevent water loss and can inhibit
the growth of some bacteria.
a) Sweat
b) Cerumen
c) Sebum
d) Mucus
c) Sebum
Which exocrine gland is primarily used for thermoregulation?
a) Sebaceous gland
b) Eccrine sweat gland
c) Apocrine sweat gland
d) Ceruminous gland
b) Eccrine sweat gland
List and briefly describe the major functions of the skin
The functions of the skin include: 1) Thermoregulation: The skin thermoregulates in
response to increased temperature by secreting sweat onto its surface and then increasing blood
flow to the surface leading to cooling of the blood. In response to low temperatures, production
of sweat is decreased and blood flow is diverted from surface to conserve heat. 2) The skin
contains 8-10% of the blood and thus serves as a blood reservoir. 3) The skin covers the body
and provides protection using keratin, lipids, secretions like oil and sweat, and immunological
defenses. 4) The skin can detect and respond to cutaneous sensations. 5) The skin helps in
excretion and absorption. 6) The skin also can synthesize vitamin D.
Briefly describe the steps in epidermal wound healing
In response to an epidermal injury, basal cells of the epidermis surrounding the wound
break contact with the basement membrane. The cells then enlarge and migrate across the
wound. The cells appear to migrate as a sheet. When epidermal cells encounter each other they
stop migrating due to contact inhibition. Migration of the epidermal cells stops completely when
each is finally in contact with other epidermal cells on all sides. Epidermal growth factor is also
secreted to stimulate the basal stem cells to divide and replace the ones that have moved into the
wound. Epidermal cell division eventually regenerates the strata of the epidermis.
Briefly describe the steps in deep wound healing
In deep wound healing, a blood clot forms during the inflammatory response and
loosely unites the wound edges. Then in the migratory phase the clot becomes a scab and
epithelial cells migrate beneath the scab to bridge the wound. Fibroblasts migrate along fibrin
threads and begin synthesizing scar tissue and damaged blood vessels begin to regrow. During
this phase, the tissue filling the wound is called granulation tissue. The proliferative phase is
characterized by extensive growth of epithelial cells beneath the scab, deposition by fibroblasts
of collagen fibers in random patterns, and continued growth of blood vessels. During the
maturation phase, the scab sloughs off once the epidermis has been restored to normal thickness.
Collagen fibers become more organized, fibroblasts decrease in number and blood vessels are
restored to normal.
