1. A/P Ch 5
Flash cards

2. What are the major regions of the skin?

3. What are the major regions of the skin?
Epidermis – outermost superficial region
Dermis – middle region
Hypodermis (superficial fascia) – deepest region

4. )
Figure 5.1

5. Reticular layer of dermis
Hair shaft
Pore
Dermal papillae
(papillary layer
of dermis)
Epidermis
Meissner's corpuscle
Free nerve ending
Reticular layer of dermis
Sebaceous (oil) gland
Dermis
Arrector pili muscle
Sensory nerve fiber
Eccrine sweat gland
Pacinian corpuscle
Hypodermis
(superficial
fascia)
Artery
Vein
Hair root
Adipose tissue
Hair follicle
Eccrine sweat
gland
Hair follicle receptor
(root hair plexus)
Figure 5.1

6. Describe the Epidermis
Composed:
Cell Types:
Cell Layers:
Main Function:

7. Describe the Epidermis
Composed: keratinized stratified squamous epithelium
Cell Layers: Stratum Corneum, Stratum Lucidum, Stratum Granulosum, Stratum Spinosum, Stratum Basale
Cell Types:keratinocytes, melanocytes, Merkel cells, and Langerhans’ cells
Main Function: protection

8. Layers of epidermis

9. What is Keratinocytes?

10. produce the fibrous protein keratin
What is Keratinocytes?
produce the fibrous protein keratin

11. What is Melanocytes?

12. produce the brown pigment melanin
What is Melanocytes?
produce the brown pigment melanin

13. What is Langerhans’ cells?

14. What is Langerhans’ cells?
epidermal macrophages that help activate the immune system

15. What are Merkel cells?

16. function as touch receptors in association with sensory nerve endings
What are Merkel cells?
function as touch receptors in association with sensory nerve endings

17. Describe the Stratum Basale

18. Describe the Stratum Basale
Deepest epidermal layer firmly attached to the dermis
Consists of a single row of the youngest keratinocytes
Cells undergo rapid division

19. Describe Stratum Spinosum

20. Describe Stratum Spinosum
Cells contain a weblike system of intermediate filaments attached to desmosomes
Melanin granules and Langerhans’ cells are abundant
“Prickly Layer”

21. Describe Stratum Granulosum

22. Describe Stratum Granulosum
Thin; three to five cell layers in which drastic changes in keratinocyte appearance occurs
Keratohyaline and lamellated granules accumulate in the cells of this layer

23. Describe the Stratum Lucidum

24. Describe the Stratum Lucidum
Thin, transparent band superficial to the stratum granulosum
Consists of a few rows of flat, dead keratinocytes
Present only in thick skin
“Clear Layer”

25. Describe the Stratum Corneum

26. Describe the Stratum Corneum
Horny Layer
Outermost layer of keratinized cells
Accounts for three quarters of the epidermal thickness
Functions include:
Waterproofing
Protection from abrasion and penetration
Rendering the body relatively insensitive to biological, chemical, and physical assaults

27. Describe the Dermis

28. Describe the Dermis
Second major skin region containing strong, flexible connective tissue
Cell types include: fibroblasts, macrophages, and occasionally mast cells and white blood cells
Composed of two layers
Papillary
reticular

29. Describe the Papillary Layer

30. Describe the Papillary Layer
Areolar connective tissue with collagen and elastic fibers
Its superior surface contains peglike projections called dermal papillae
Dermal papillae contain capillary loops, Meissner’s corpuscles, and free nerve endings

31. Describe the Reticular Layer

32. Describe the Reticular Layer
80% of the thickness of the skin
Collagen fibers in this layer add strength and resiliency to the skin
Elastin fibers provide stretch-recoil properties

33. What is the Hypodermis?

34. What is the Hypodermis? Subcutaneous layer deep to the skin
Composed of adipose and areolar connective tissue
Fatty Layer

35. What three pigments contribute to skin color

36. What three pigments contribute to skin color?
Melanin – yellow to reddish-brown to black pigment, responsible for dark skin colors
Freckles and pigmented moles – result from local accumulations of melanin
Carotene – yellow to orange pigment, most obvious in the palms and soles of the feet
Hemoglobin – reddish pigment responsible for the pinkish hue of the skin

37. What’s the function of sweat glands?

38. What’s the function of sweat glands?
Different types prevent overheating of the body; secrete cerumen and milk

39. Describe Eccrine Sweat Glands?

40. Describe Eccrine Sweat Glands?
found in palms, soles of the feet, and forehead

41. Describe Apocrine sweat glands

42. Describe Apocrine sweat glands
found in axillary and anogenital areas
(arm pits, areola of nipples, and genitals)

43. Describe Ceruminous glands

44. Describe Ceruminous glands
modified apocrine glands in external ear canal that secrete cerumen

45. Describe Mammary glands
specialized sweat glands that secrete milk

46. Glands

47. Describe Sebaceous Glands

48. Describe Sebaceous Glands
Simple alveolar glands found all over the body
Soften skin when stimulated by hormones
Secrete an oily secretion called sebum

49. Describe Hair

50. Describe Hair
Filamentous strands of dead keratinized cells produced by hair follicles
Contains hard keratin
Pigmented by melanocytes at the base of the hair

51. Functions of hair include

52. Functions of hair include
Helping to maintain warmth
Alerting the body to presence of insects on the skin
Guarding the scalp against physical trauma, heat loss, and sunlight

53. Hair is distributed over the entire skin surface except:

54. Hair is distributed over the entire skin surface except:
Palms, soles, and lips
Nipples and portions of the external genitalia

55. What is Vellus Hair?

56. pale, fine body hair found in children and the adult female
What is Vellus Hair?
pale, fine body hair found in children and the adult female

57. What is Terminal hair?

58. coarse, long hair of eyebrows, scalp, axillary, and pubic regions
What is Terminal hair?
coarse, long hair of eyebrows, scalp, axillary, and pubic regions

59. Describe Hair thinning and balding

60. Describe Hair thinning and balding
Alopecia – hair thinning in both sexes
True, or frank, baldness
Genetically determined and sex-influenced condition
Male pattern baldness – caused by follicular response to DHT

61. Structure of a Nail

62. Functions of the Integumentary System

63. Functions of the Integumentary System
Protection
Body temperature regulation
Cutaneous sensation
Metabolic functions
Blood reservoir
Excretion

64. What does the skin protect from?

65. What does the skin protect from?
chemical, physical, and mechanical barrier

66. How is Body Temperature is accomplished?

67. How is Body Temperature is accomplished?
Dilation (cooling) and constriction (warming) of dermal vessels
Increasing sweat gland secretions to cool the body

68. Explain Cutaneous Sensation

69. Explain Cutaneous Sensation
exoreceptors sense touch and pain

70. Describe Metabolic Functions

71. Describe Metabolic Functions
Synthesis of vitamin D in dermal blood vessels

72. Describe the Blood Reservoir function of the skin

73. Describe the Blood Reservoir function of the skin
skin blood vessels store up to 5% of the body’s blood volume

74. What does the skin Excrete?

75. What does the skin Excrete?
limited amounts of nitrogenous wastes are eliminated from the body in sweat

76. Briefly describe Skin Canser

77. Briefly describe Skin Canser
Most skin tumors are benign and do not metastasize
A crucial risk factor for non-melanoma skin cancers is the disabling of the p53 gene
Newly developed skin lotions can fix damaged DNA

78. What are the 3 major types of skin cancer?

79. What are the 3 major types of skin cancer?
Basal cell carcinoma
Squamous cell carcinoma
Melanoma

80. Describe Basal Cell Carcinoma

81. Describe Basal Cell Carcinoma
Least malignant and most common skin cancer
Stratum basale cells proliferate and invade the dermis and hypodermis
Slow growing and do not often metastasize
Can be cured by surgical excision in 99% of the cases

82. Describe Squamous Cell Carcinoma

83. Describe Squamous Cell Carcinoma
Arises from keratinocytes of stratum spinosum
Arise most often on scalp, ears, and lower lip
Grows rapidly and metastasizes if not removed
Prognosis is good if treated by radiation therapy or removed surgically

84. Describe Melanoma

85. Describe Melanoma
Cancer of melanocytes is the most dangerous type of skin cancer because it is:
Highly metastatic
Resistant to chemotherapy
Chance of survival is poor if the lesion is over 4 mm thick

86. Skin cancers

87. What characteristics does Melanoma Have?

88. What characteristics does Melanoma Have?
(ABCD rule)
A: Asymmetry; the two sides of the pigmented area do not match
B: Border is irregular and exhibits indentations
C: Color (pigmented area) is black, brown, tan, and sometimes red or blue
D: Diameter is larger than 6 mm (size of a pencil eraser)

89. Describe a First Degree Burn

90. Describe a First Degree Burn
only the epidermis is damaged
Symptoms include localized redness, swelling, and pain

91. Describe a Second Degree Burn

92. Describe a Second Degree Burn
Epidermis and upper regions of dermis are damaged
Symptoms mimic first degree burns, but blisters also appear

93. Describe a Third Degree Burn
Entire thickness of the skin is damaged
Symptoms: Burned area appears gray-white, cherry red, or black; there is no initial edema or pain (since nerve endings are destroyed)

94. What does the Rule of Nines estimate?

95. What does the Rule of Nines estimate?
Estimates the severity of burns
Burns considered critical if:
Over 25% of the body has second-degree burns
Over 10% of the body has third-degree burns
There are third-degree burns on face, hands, or feet

96. Rule of Nines

97. Explain Fetal Skin Development

98. Explain Fetal Skin Development
Epidermis develops from ectoderm
Dermis and hypodermis develop from mesoderm
Lanugo – downy coat of delicate hairs covering the fetus
Vernix caseosa – substance produced by sebaceous glands that protects the skin of the fetus in the amnion

99. Describe skin development (Adolescent – Adult)

100. Describe skin development (Adolescent – Adult)
Skin and hair become oilier and acne may appear
Skin shows the effects of cumulative environmental assaults around age 30
Scaling and dermatitis become more common

101. Describe skin development (old-age)

102. Describe skin development (old-age)
Epidermal replacement of cells slows and skin becomes thinner
Skin becomes dry and itchy
Subcutaneous fat layer diminishes, leading to intolerance of cold
Decreased elasticity and loss of subcutaneous tissue leads to wrinkles
Decreased numbers of melanocytes and Langerhans’ cells increase the risk of skin cancer

103. Questions from the Textbook and
Lab Homework

104. What type of granules are extruded from the kerationocytes prevent water loss by diffusion through the epidermis?

105. What type of granules are extruded from the kerationocytes prevent water loss by diffusion through the epidermis?
Lamellated

106. What produces the fibers in the dermis?

107. What produces the fibers in the dermis?
Fibroblast

108. What type of glands respond to rising androgen levels?

109. What type of glands respond to rising androgen levels?
Apocrine glands

110. Phagocytic cells that occupy the epidermis are called?

111. Phagocytic cells that occupy the epidermis are called?
Langerhan’s Cells

112. A unique touch receptor formed from a stratum basale cell and nerve fiber is a …..

113. A unique touch receptor formed from a stratum basale cell and nerve fiber is a …..
Merkel disc

114. What layer is present in thick skin but not in thin skin?

115. What layer is present in thick skin but not in thin skin?
Stratum Lucidum

116. What cell-to-cell structures hold the cells of the stratum spinosum tightly together?

117. What cell-to-cell structures hold the cells of the stratum spinosum tightly together?
Desmosomes

118. What substance is manufactured in the skin that plays a role in calcium absorption in the body?

119. What substance is manufactured in the skin that plays a role in calcium absorption in the body?
Vitamin D

120. Which epidermal cell type is most numerous?

121. Which epidermal cell type is most numerous?
Keratinocyte

122. which cell functions as part of the immune system

123. which cell functions as part of the immune system
An epidermal dendritic cell

124. the epidermis provides a physical barrier due largely to the presence of

125. the epidermis provides a physical barrier due largely to the presence of
Collagen

126. skin color is determined by

127. skin color is determined by
-the amount of blood
-pigments
-oxygenation level

128. the sensations of touch and pressure are picked up by receptors located in

129. the sensations of touch and pressure are picked up by receptors located in
The stratum spinosum

130. Skin surface markings that reflect points of tight dermal attachment to underlining tissues are called?

131. Skin surface markings that reflect points of tight dermal attachment to underlining tissues are called?
Flexure Lines