BIOL235; Chapter 5

Q 5.82: The major part of a hair shaft is the ____________.

Cortex

Q 5.91: Which layer of hair contains elongated cells?

Cortex

Q 5.93: Which epidermal layer is found only in thick skin?

stratum lucidum

Q 5.158: What is the maturation phase preceded by deep wound healing?

proliferative phase

Q 5.161: Fibroblasts deposit collagen fibers in random patterns during which phase of deep wound healing?

proliferative phase

Q 5.95: The epidermal layer found in thin skin can range in thickness from

0.1 - 0.15 mm

Q 5.101: The epidermis of thick skin can range from _________ in thickness.

0.6 — 4.5 mm

Q 5.129: Approximately how much water evaporates through the skin each day?

500 — 600 mL

Q 5.125: In a sedentary person, about ___________ of water is lost as sweat.

600 mL

Q 5.75: Which of the following is not true of the papilla of the hair? A: It contains hair matrix. B: It contains areolar tissue. C: It contains blood vessels. D: It is found in the bulb.

A: It contains hair matrix.

Q 5.51: Which of the following is true about skin color? A: Skin color of light-skinned people is strongly influenced by the oxygen content of hemoglobin. B: Skin color of light-skinned people is due mainly to carotene. C: The enzyme melanase is used by melanosomes to synthesize melanin. D: Melanin production increases in response to mechanical stress on the skin

A: Skin color of light-skinned people is strongly influenced by the oxygen content of hemoglobin.

Q 5.50: Which of the following is not true of epidermal ridges? A: form during the last trimester of development B: increase tactile sensitivity by increasing the density of Meissner corpuscles C: combine with sweat to form fingerprints D: create a strong bond between the epidermis and dermis in areas of high stress

A: form during the last trimester of development

Q 5.58: Desmosomes bind keratinocytes to ______. A: other keratinocytes B: melanocytes C: the basement membrane D: the hypodermis E: stem cells

A: other keratinocytes

Q 5.78: The base of each hair and its surrounding dermal sheath is the_____

Bulb

Q 5.164: During epidermal wound healing, epidermal cells stop migrating when they encounter one another, a response called...

Contact inhibition

Q 5.52: Which of the following is not true about melanin? A: Melanin production increases in response to DNA damage. B: Exposure to UV radiation increases enzymatic activity in melanosomes. C: Melanin neutralizes free radicals. D: Melanin reflects UV radiation back out of the epidermis.

D: Melanin reflects UV radiation back out of the epidermis.

Q 5.107: Epidermal ridges are more prominent in thick skin due to the presence of more numerous... A: sebaceous glands B: arrector pili muscles C: sudoriferous glands D: dermal papillae organized in parallel rows E: sensory receptors

D: dermal papillae organized in parallel rows

Q 5.76: Which layer of hair consists of two or three rows of irregularly shaped cells? A: internal root sheath B: cuticle C: cortex D: medulla

D: medulla

Q 5.77: Which layer of hair is sometimes absent in thinner hair? A: cortex B: cuticle C: internal root sheath D: medulla

D: medulla

Q 5.54: Which layer of the epidermis contains flattened clear, dead keratinocytes? A: stratum spinosum B: stratum granulosum C: stratum basale D: stratum lucidum E: stratum corneum

D: stratum lucidum

Q 5.89: The arrector pili attaches to the _______ of the hair follicle.

Dermal root sheath

Q 5.118: Approximately 15% of the total blood in a resting adult flows through dermal blood vessels. True or False?

False (answer is 8 - 10%)

Q 5.60: Lamellar granules assemble keratin intermediate filaments into keratin. True or False?

False

Q 5.53: About 75% of epidermal cells are keratinocytes. True or False?

False (90% are keratinocytes)

Q 5.62: The predominant cells of the dermis are __________.

Fibroblasts

Q 5.150: The combination of blood clot, fibroblasts, and an extensive capillary network in early dermal repair is called

Granulation Tissue

Q 5.72: The internal and external root sheath make up the______

Hair follicle

Q 5.70: The sends impulses when a hair shaft is moved.

Hair root plexus

Q 5.98: Thick skin is characterized as_____skin.

Hairless

Q 5.96: Thin skin is characterized as_______skin.

Hairy

Q 5.123: Intraepidermal and general macrophages carry out_____functions of the skin.

Immunity

Q 5.166: The epidermis is restored to normal thickness during which phase of deep wound healing?

Maturation phase

Q 5.56: Mary has severe anemia; she will likely exhibit ___________.

Pallor

Q 5.153: Extensive growth of epithelial cells beneath the scab occurs during which phase of deep wound healing?

Proliferation stage

Q 5.83: Cells of the hair matrix stop dividing during which growth stage?

Regression

Q 5.94: In thin skin, the stratum corneum and the stratum_____are thinner when compared to thick skin.

Spinosum

Q 5.66: In which layer of the epidermis do the keratinocytes shrink and pull apart when prepared for microscopic observation?

Stratum Spinosum

Q 5.81: Mammary glands are modified___________glands.

Sudoriferous

Q 5.108: Dermal papillae are not prominently featured in_______skin.

Thin

Q 5.135: Some drugs can be delivered via a "skin patch"; this method is referred to as_________drug administration.

Transdermal

Q 5.55: Melanocytes are found in mucous membranes. True or False?

True

Q 5.74: Short, fine, pale hairs that cover most of the body of a newborn are called are called_________hairs.

Vellus

Q 5.136: Identify the substance that is directly formed in the skin with UV light.

Vitamin D

Q 5.63: The dermis is dominated by_______and elastic connective tissue fibers.

collagan

Q 5.167: An injury occurs and the wound heals but the scar is still visible. What is this is an example of?

hypertrophic scar

Q 5.151: During which phase of deep wound healing does a blood clot form and loosely unite the wound edges?

inflammatory phase

Q 5.157: During which phase of deep wound healing do macrophages phagocytize microbes?

inflammatory phase

Q 5.162: During which phase of deep wound healing are mesenchymal cells delivered to the wound area?

inflammatory phase

Q 5.156: Fibroblasts begin synthesizing scar tissue during which phase of deep wound healing?

migratory phase

Q 5.163: During which phase of deep wound healing does the blood clot become a scab?

migratory phase

Q 5.100: An increase in the mechanical stress on the skin increase which layer of the epidermis?

stratum corneum

Q 5.97: Which layer of epidermis is the greatest contributor to the thickness of skin?

stratum corneum

Q 5.102: Sudoriferous glands are found in higher numbers in______skin.

thick

Q 5.57: Keratin intermediate filaments are also known as________

tonofilaments.