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Medicine > Dermatology - Intro To Dermatology > Flashcards

Dermatology - Intro To Dermatology Flashcards

1
Q

Skin is composed of three layers

A

Epidermis
Dermis
Subcutaneous fat (panniculus)

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2
Q

Composed of viable keratinocytes covered by a layer of keratin

A

Epidermis

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3
Q

Principal component of dermis

A

Fibrillar structural protein, collagen

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4
Q

Composed of lobules of lipocytes separated by collagenous septa that contain neurovascular bundles

A

Panniculus or subcutaneous tissue

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5
Q

Epidermis is thickest on the

A

Palms and soles

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6
Q

Epidermis thinest on

A

Eyelid

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7
Q

Dermis thickest on

A

The back

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8
Q

Subcutaneous fat is generous in these areas

A

Abdomen and buttocks

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9
Q

Subcutaneous fat thinnest on the

A

Nose and sternum

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10
Q

First few weeks of life, fetus covered by a layer of

A

Nonkeratinizing cuboidal cells (periderm)

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11
Q

Adnexal stuctures originate as downgrowths of

A

Developing epidermis

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12
Q

Adnexal structures first develop during this time

A

Third month of life

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13
Q

Apocrine sweat units develop from this portion of follicular epithelium

A

Upper portion of the follicular epithelium

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14
Q

Sebaceous glands develop from this portion of follicular epithelium

A

Midregion

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15
Q

Adnexal structures appear first in

A. Cephalic
B. Caudal portion of the fetus

A

Cephalic to caudal

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16
Q

Three basic cell types of adult epidermis

A

Keratinocytes
Melanocytes
Langerhans cells

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17
Q

Additional cell that can be found in the basal layer of palms and soles, oral and genital mucosa, nail bed and follicular infundibula

A

Merkel cells

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18
Q

Location of merkel cells (layer)

A

Basal layer

Directly above the basement membrane zone

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19
Q

Contain intracytoplasmic dense core neurosecretory-like granules
Associated with neurites, act as slow-adapting touch receptors

A

Merkel cells

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20
Q

Have direct connections with adjacent keratinocytes by desmosomes
Contain a paranuclear whorl of intermidiate keratin filaments

A

Merkel cells

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21
Q

Exhibits a paranuclear dot pattern

A

Merkel cells

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22
Q

Label for neuroendocrine markers such as chromogranin and synaptophysin

A

Merkel cells

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23
Q

Squamous cells

A

Keratinocytes

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24
Q

Principal cells of the epidermis

A

Keratinocytes/ squamous cells

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25
Q

Keratinocytes/ squamous cells

Germ cell origin

A

Ectoderm

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26
Q

Have a specialized function of producing keratin

A

Keratinocytes

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27
Q

Complex filamentous protein that forms as surface coat (stratum corneum), structural protein of hair and nails

A

Keratin

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28
Q

Critical for normal functioning of the epidermis, its mutation are recognized causes of skin disease

A

Keratin

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29
Q

Mutation of genes for these keratin are associated with epidemolysis bullosa simplex

A

Keratins 5 and 14 (EBS)

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30
Q

Mutation of genes for these keratin are associated with epidermolytic hyperkeratosis

A

1, 10 (EH)

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31
Q

Epidermis sublayers

A 
Stratum germinativum
Stratum spinosum
Stratum granulosum
Stratum lucidum ( palms and soles)
Stratum corneum
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32
Q

Innermost basal layer of epidermis

A

Stratum germinativum

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33
Q

Malpighian or prickle layer

A

Stratum spinosum

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34
Q

Granular layer

A

Stratum granulosum

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35
Q

Horny layer

A

Stratum corneum

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36
Q

Pale clear to pink layer

Palms and soles

A

Stratum lucidum

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37
Q

When the skin is scratched or rubbed, these layer thickens or forms

A

Stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum (thick and compact)

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38
Q

Regulate epidermal differentiation

A

Histones

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39
Q

Suppresses expression of profilaggrin

A

Histone deacetylation

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40
Q

Provide a reservoir for regeneration of epidermis

A

Slow-cycling stem cells

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41
Q

Abnormal keratinization can manifest as

A

Parakeratosis
Corps ronds
Grains

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42
Q

Appear in the interface between granular and cornified cell layers

A

Lamellar granules (odland bodies or membrane-coating granules)

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43
Q

Demonstrate abnormal lamellar granules

A

Lamellar ichthyosis and Flegel’s hyperkeratosis

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44
Q

Contribute a water-barrier function to skin

Found in topical products mean to restore epidermal barrier

A

Glycolipids (ceramides)

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45
Q

Lamellar bodies for, abnormally in the absence of

A

Critical ceramides (glucosylceramide) or disproportion of critical lipids

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46
Q

Desmosomal adhesions depends on

A

Cadherins, calcium - dependent desmogleins, desmocollins

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47
Q

Antibodies to caderins, calcium-dependent desmogleins, desmocollins result in

A

Immunobullous diseases

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48
Q

Desmogleins function

A

Adhesion

Differentiation

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49
Q

Profilaggrin is contained in keratohyaline granules in this layer

A

Granular zone

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50
Q

Converstion of profilaggrin to filaggrin takes place in

A

Granular layer

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51
Q

Characterized by diminished or absent granular layer contributing to retention hyperkeratosis

A

Ichthyosis vulgaris

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52
Q

Results in the formation of soft, flexible keratin

A

Keratohyalin

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53
Q

Has an active role in the immune fx of the skin

A

Keratinocytes

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54
Q

In the presence of Allergic contact dermatitis

Keratinocytes secrete

A

Cytokines, inflammatory mediators (TNF-alpha)

Express on their surface: intercellular adhesion molecule 1 (ICAM-1), major histocompatibility complex (MHC)

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55
Q

Melanocytes are derived from

A

Neural cresy

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56
Q

Melanocytes can be found in the fetal epidermis by ___ wk of development

A

8th

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57
Q

Differences in skin color is due to

A

Number, size, distribution of melanosomes or pigment granules within keratinocytes

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58
Q

Dendritic cell, lacking cell-cell junctions, lacking tonofilaments, cell with ample amphiphilic cytoplasm

A

Melanocye

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59
Q

Synthesize in the golgi zone of the melanocyte

A

Melanosomes

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60
Q

Rounder melanocytes, more pheomelanin

A

Red hair

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61
Q

Loss off fx mutation in MC1R bring about this change

A

Eumelanin to pheomelanin

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62
Q

Key components of the innate immune system of the skin

A

Antimicrobial peptides (cathelicidin, B defensins)

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63
Q

Protect against infection
Role in control of pigmentation
Implicated in the pathogenesis of atopic dermatitis

A

Cathelicidin, Beta defensins

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64
Q

small cationic proteins important to innate and adaptive immue system,

A

B-defensin 3

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65
Q

Also functions as a melanocortin receptor ligand

A

B-defensin 3

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66
Q

Eumelanin production is optimal at this pH

A

6.8

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67
Q

Evidence of keratinocyte photodamage

A

Thymidine dimer formation

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68
Q

Affected skin becomes white because of destruction of melanocytes

A

Vitiligo

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69
Q

Melanocytes number normal

Unable to synthesize fully pigmented melanosomes because of defects in enzymatic formation of melanin

A

Albinism

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70
Q

Demonstrate basilar hyperpigmentation and prominent melanin within stratum corneum

A

Black sunburn or ink spot lentigines

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71
Q

Benign proliferations of melanocytes

A

Nevi

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72
Q

Malignant counterpart of nevi

A

Melanomas

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73
Q

Effect on pigmentation of
Toll-like receptors
Bacterial lipopolysaccharides

A

Inc. Pigmentation

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74
Q

Normally found scattered in the stratum spinosum

A

Langerhans cells

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75
Q

Langerhans cells found in this layer

A

Stratum spinosum

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76
Q

Cells not connected to adjacent keratinocytes by the desmosomes

A

Melanocytes

Langerhans cells

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77
Q

Highest density of langerhans cells in the oral mucosa

A

Oral mucosa (vestibular region)

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78
Q

Lowest density of langerhans cells in the oral mucosa

A

Sublingual region

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79
Q

Stain specific for langerhans cells

A

Gold chloride

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80
Q

Characterized by a folded nucleus and intracytoplasmic organelles called birbeck granules

A

Langerhans cells

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81
Q

Langerhans cells contain these organelles

A

Birbeck granules

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82
Q

Fully developed form: organelles are rod shaped with a vacuole with one end, resembling a tennis racquet

A

Langerhans cells

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83
Q

Origin of langerhans cells

A

Monocyte-macrophage lineage, originate in the bone marrow

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84
Q

Provides recognition, uptake, processing, and presentation of antigens to T lymphocytes
Induction of delayed-type sensitivity

A

Langerhans cells

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85
Q

Plays a critical role in the langerhans cell maturation and migration

A

Hyluronan (hyaluronic acid)

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86
Q

Depletes langerhans cells

A

UV radiation

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87
Q

If skin loses langerhans cells, it loses this ability

A

To be sensitized (immune tolerance)

Because macrophage found in epidermis 72 h after UV B irradiation produce IL 10 (downregulates immune response)

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88
Q

Junction of epidermis and dermis is formed by

A

Basement membrane zone (dermoepidermal junction)

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89
Q

Basement membrane zone composed of 4:

A

Plasma membranes of basal cells with hemidesmosomes
Lamina lucida
Lamina densa (basal lamina)
Fibrous components assoc. with basal lamina - anchoring fibrils, dermal microfibrils, collagen fibers

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90
Q

basal lamina is synthesized by

A

Basal cells of the epidermis

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91
Q

Major component of basal lamina

A

Type IV collagen

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92
Q

Major component of anchoring fibrils

A

Type VII collagen

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93
Q

Two makor hemidesposomal proteins of dermoepidermal junction

A

BP230 (bullous pemphigoid antigen 1)

BP180 (bullous pemphigoid antigen 2, type XVII collagen)

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94
Q

Considered to be a porous semipermeable filter, which permits exchange of cells and fluid between the dermis and epidermis

A

BMZ

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95
Q

Serves as a structural support for the epidermis and holds the epidermis and dermis together

A

BMZ

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96
Q

Helps regulate growth, adhesion and movement of keratinocytes and fibroblasts, as well as apoptosis

A

BMZ

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97
Q

How does BMZ regulate fx

A

Activation of integrins and syndecans

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98
Q

Loss of fx of extracellular matrix protein 1 results to (in lipoid proteinosis)

A

Reduplication of basement membrane

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99
Q

Epidermal Appendages

A

Eccrine, apocrine glands
Ducts
Pilosebaceous units constitute adnexa

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100
Q

Signaling critical for hair development

A

Hedgehog signaling

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101
Q

Abnormalities in this pathway contribute to formation of

A

Pilar tumors

Basal cell carcinoma

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102
Q

Absence of hedgehog signaling results to

A

Embryonic hair germs may develop instead into modified sweat glands or mammary epithelium

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103
Q

T/F

All adnexa can function as reserve epidermisT

A

T

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104
Q

Which reepithelialize more rapidly due to abundance of adnexa

A. Face, scalp
Vs
B. Back

A

A. Face and scalp

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105
Q

Intraepidermal spiral duct, which opens directly onto the skin surface

A

Eccrine sweat units

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106
Q

Acrosyringium

A

Eccrine sweat units

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107
Q

Composed of small polygonal cells with a central round nucleus, surrounded by ample pink cytoplasm

A

Acrosyringium

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108
Q

Straight dermal portion of the duct is composed of

A

Double layer of cuboidal epithelial cells

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109
Q

Lining of dermal portion of acrosyringium

A

lined by eosinophilic cuticle on its luminal side

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110
Q

Coiled secretory portion of acrosyringium is found in this layer

A

Superficial panniculus

Except in the back (deep dermis)

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111
Q

acrosyringium

Two types of secretory cells

A

Large, pale, glycogen rich cells

Smaller, darker-staining cells

112
Q

acrosyringium

Which type of secretory cell is thought to initiate sweat formation

A

Pale, glycogen-rich cells

113
Q

acrosyringium

Type of secretory cell that active reabsorbs sodium, modifying the sweat from isotonic to hypotonic

A

Darker cells

114
Q

In humans, _______ units are found in virtually all skin sites

A

eccrine sweat units

115
Q

In most mammals, this gland is the major sweat gland

A

Apocrine

116
Q

What mediates physiologic secretion of swear

A

Cholinergic innervation

117
Q

Stimulus increased sweating

A

Heat

Emotional stress

118
Q

This type of sweating involves a biphasic response, with initial hyperpolarization and secondary depolarization mediated by activation of Ca and Cl ion conductance

A

Cholinergic sweatinf

119
Q

Sweating
Involves monophasic depolarization
Dependon on GCI (cystic fibrosis transmembrane conductance regulator)

A

Adrenergic secretion

120
Q

This type of sweating is absent in pt with CF

A

No adrenergic secretion

121
Q

This hormone also play a role in stimulating eccrine secretion

A

Vasoactive intestinal polypeptide

122
Q

Apocrine units develop as outgrowths of

A

Infundibular or upper portion of hair follicle (not surface epidermis)

123
Q

T/F
Although immature apocrine units are found covering the entire skin surface of the human fetus, these regress and are absent by the time the fetus reaches term.

A

T

124
Q

Straight excretory potion of apocrine duct composed of

A

Double layer of cuboidal epithelial cells

125
Q

Apocrine sweat glands open into

A

Infundibular portion of hair follicle

126
Q

Coiled secretory gland of aprocrine glands is located at the

A

Junction of dermis and subcutaneous fat

127
Q

Lining of the coiled secretory gland of apocrine

A

Single layer of cells (columnar to cuboidal)

128
Q

More widely dilated than eccrine coils

A

Apocrine coils

129
Q

Sweat stains more deeply red in H&E sections

A

Apocrine coilds

130
Q

Pale pink sweat stains H&E

A

Eccrine

131
Q

Decapitation secretion (apex)

A

Apocrine sweat glands

132
Q

Apocrine secretion is mediated by

A

Adrenergic innervation
Catecholamines (circulating, adrenomedullary origin)
VIP

133
Q

Episodic excretion, continuous secretion

A

Apocrine

134
Q

Function of apocrine sweat glands in humans

A

No known fx

135
Q

Apocrine fx other anmials

A

Protective, sexual, thermoregulation

136
Q

Apocrine generally found in the ff sites

A 
Axillae,
Areolae
Anogenital region
External auditory canal (ceruminous glands)
Eyelids (glands of Moll)
Stroma of sebaceous nevus of Jasasshon
137
Q

Apocrine glands do not begin to fx until

A

Puberty

138
Q

Upper bud of fetal follicle develops into

A

Sebaceous glands

139
Q

Lower bud of fetal follicle develops into

A

Becomes attachment of the arrector pili muscle

140
Q

A third epithelial bud develops from the opposite side of the follicle above the lvel of the sebaceous gland anlage and gives rise to ____

A

apocrine gland

141
Q

Uppermost portion of the follicle, which extends from its surface opening to the entrance of the sebaceous duct is called

A

Infundibular segment

142
Q

Portion of the follicle betwen sebaceous duct and insertion of arrector pili muscle is

A

Isthmus

143
Q

Throughout life, in the follicle, this portion undergoes cycles of involution and regeneration

A

Inferior portion

144
Q

Hair follicles develop sequentially in rows of

A

Three

145
Q

Are surrounded by the appearance of two secondary follicles

A

Primary follicles

146
Q

Where to the arrector pili muscles interconnect within the follicular unit

A

Isthmus

147
Q

Move together as hair grows

A

Hair shaft and inner root sheath until the fully keratinized inner rooth sheath sheds at the level of isthmus

148
Q

Portion of the follicle that is permanent

A

Upper two (infundibulum, isthmus)

149
Q

This segment is completely replaced with each new cycle of hair growth

A

Inferior segment

150
Q

Active growth phase of hair

A

Anagen

151
Q

Anagen lasts

A

3-5 years

152
Q

% of scalp hairs in anagen phase

A

85-90%

153
Q

Scalp anagen hairs grow at a rate of

A

0.33 mm/day

154
Q

Catagen / involution lasts

A

2 weeks

155
Q

Resting phase of hair

A

Telogen

156
Q

Telogen lasts

A

3-5 months

157
Q

AIDS effect on anagen phase

A

Prolonged

158
Q

Synchronous termination of anagen or telogen results in

A

Telogen effluvium

159
Q

is when some stress causes hair roots to be pushed prematurely into the resting state

A

Telogen effluvium

160
Q

Telogen effluvium can be induced by

A

Febrile illness, surgery, weight loss

161
Q

___ months after pregnancy, a more pronounced effluviun is noted

A

3-5 months

162
Q

This hair cycle is characterized by a pigmented bulb and inner root sheath

A

Growing anagen hair

163
Q

chemotherapy affects this cycle

A

Anagen

164
Q

Best identified by presence of apoptotic cells in the outer root sheath

A

Catagen hairs

165
Q

Have nonpigmented bulb with a shagging lower border

A

Telogen club hairs

166
Q

Scalp hair of white people is shaped

Pubic hair, beard and eyelashes are shaped

A

Round

Oval

167
Q

Scalp hair of black people are

A

Oval

Which causes it to be curly

168
Q

Uncombable hair is

A

Triangular with a central canal

169
Q

Hair shape is partially controlled by

A

Trichohyalin gene

170
Q

Hair color depends on

A

Degree of melanization

Distribution of melanosomes within the hair shaft

171
Q

Larger melanosomes are found in the hair of

A

Black persons

172
Q

Smaller melanosomes which are aggregated within membrane bound complexes are found in the hair of

A

White persons

173
Q

Graying of hair results from

A

Decreased number of melanocytes (fewer melanosomes)

174
Q

Premature graying is related to

A

Exhaustion of the melanocyte stem cell pool

175
Q

Sebaceous glands are formed as an outgrowth ofrom

A

Upper portion of hair follicle

176
Q

Composed of lobules of pale-staining cells with abundant lipid droplets in their cytoplasm
Adnexa

A

Sebaceous glands

177
Q

Lined by a red cuticle that undulates sharply ina pattern resembling shark’s teeth

A

Sebaceous duct

178
Q

Sebaceous glands are found in greatest abundance on the

A

Face, scalp

179
Q

Sebaceous glands are not found in

A

Palms and soles
Hair follicles of the tarsal plate of the eyelids (meibomian glands), buccal mucosa, vermilion border of the lip (fordyce spots), prepuce, mucosa lateral to the penile frenulum (Tyson glands), labia minora, female areola (Montgomery tubercles)

180
Q

Adnexa functionally and anatomically related to

A

Hair follicle

181
Q

Unique secretory products of sebaceous glands

A

Wax esters

Squalene

182
Q

Can reduce squalene levels produced by sebaceous glands

A

Antihistamines

183
Q

Fx of skin lipids

A 
Barrier fx
Antimicrobial properties (sphingoid bases from epidermal ceramides and fatty acids from sebaceous triglycerides)
184
Q

Protect the fingertip from trauma

A

Nails

185
Q

Leads to the formation of nail plate

A

Matrix keratinization

186
Q

Fingernails grow an average

A

0.1 mm/day

187
Q

How many months does it take to replace a complete nail plate

A

4-6 months

188
Q

Growth rate is much slower for this nail

A

Toe naikl (12-18 months)

189
Q

Keratin types found in the hair

A

Epidermal and hair types, with hair types predominating

190
Q

This keratin is only present in nail isthmus

A

Keratin 10

191
Q

Demonstrate widening of intercellular space between nail keratinocytes on electron microscopy

A

Brittle nails

192
Q

Rete pegs that resemble an egg crate

A

Skin

193
Q

True parallel rete ridges

A

Nail bed

194
Q

Nail cuticle is formed by keratinocytes of

A

Proximal nailfold

195
Q

Nail plate is formed by

A

Matrix keratinocytes

196
Q

Distal portion of the nail matrix

A

Lunula

197
Q

Endogenous pigments tend to follow the contour of

A

Lunula

198
Q

Exogenous pigments follow the

A

Contour of the cuticle

199
Q

Dorsal nail plate is formed by

A

Proximal matrix

200
Q

Ventral nail plate is formed by

A

Distal matrix, with contribution from nail bed

201
Q

Melanocytes derive from

A

Neural crest

202
Q

Nerves derive from

A

Neural crest

203
Q

Dermis derived from

A

Mesodermal

204
Q

Dermis as dendritic-shaped cells containing mucopolysaccharide (precursors of fibroblasts)
Week of fetal life

A

6th week

205
Q

Week of fetal life

Fibroblasts are actively synthesizing reticulum fibers, elastic fibers, collagen

A

12th week

206
Q

Vascular network develops
Fat cells appeared beneath the dermis
Week of fetal life

A

24th week

207
Q

This signaling is critical for the differentiation of ventral versus dorsal dermis

A

Wnt/ Beta catenin signaling

208
Q

Serves as a scaffold for the adnexal structures

A

Dermis

209
Q

Dermis composed of small collagen bundles that stain deeply red

A

Infant dermis

210
Q

Dermis with few fibroblasts persist, coollagen bundles are thick, stain pale red

A

Adult dermis

211
Q

Two populations of dermal dendritic cells are noted

A

Factor XIIIa - positicve dermal dendrocytes

CD34+ dermal dendrocytes

212
Q

Dermal dendritic cell

Gives rise to dermatofibromas, angiofibromas, acquired digital fibrokeratomas, pleomorphic fibromas, fibrous papules

A

Factor XIIIa - positive dermal dendrocytes

213
Q

This dendrocyte are accentuated around hair follicles but exist throughout the dermis

A

CD34+ dermal dendrocytes

214
Q

Dendrocyte that disappear from the dermis early in the course of morphea

A

CD34+ dermal dendrocytes

215
Q

Rare skin condition that causes painless, discolored patches on your skin
Skin changes appear on the abdomen, chest, or back
It tends to affect only the outermost layers of the skin

A

Morphea

216
Q

Tx for morphea that allows CD34+ dermal dendrocytes to reappear

A

UVA1 light treatment

217
Q

Principal component of dermis is the collagen

A

Collagen

218
Q

Represents 70% of the dry weight of the skin

A

Collagen

219
Q

Amino acids in collagen

A

Hydroxyproline
Hydroxylysine
Glycine

220
Q

Collagen type

Dermis

A

Type I collagen

221
Q

dermis below the lvel of post-capillary venule

A

Reticular dermis

222
Q

Collagen expressed in the reticular and papillary dermis

A

Collagen I mRNA and collagen III mRNA

223
Q

What downregulates collagen production in dermis

A

UV light (photoaging)

224
Q

Type collagen

BMZ

A

Type IV

225
Q

Type collagen anchoring fibrils

A

Type VII

226
Q

Type IV and Type VII produced predominately by

A

Keratinocytes

227
Q

Collagen
Dystrophic epidermolysis bullosa
Acquired epidermolysis bullosa

A

Type VII

228
Q

Produces elastic fibers, ground substance of dermis (glycosaminoglycans, acid mucopolysaccharides)

A

Fibroblast

229
Q

Consist of two components: protein filaments + elastin

A

Elastic fibers

230
Q

AA unique to elastic fibers

A

Desmosine and isodesmosine

231
Q

Fine elastic fibers

A

Papillary dermis

232
Q

Coarse elastic fibers

A

Reticular dermis

233
Q

Minor component of normal dermis but is a major mucopolysaccharide that accumulates in pathologic state

A

Hyaluronan

234
Q

Major stress-resistant material of the skin

A

Collagen

235
Q

Contribute little to resisting deformation and tearing of the skin but have a role in maintaing elasticity

A

Elastic fibers

236
Q

Term generally used to refer to a clinically heterogenous group of autoimmune diseases including lupus erythematosus, scleroderma, dermatomyositis

A

Connective tissue disease

237
Q

Involves the most visible collagen abnormalities, collagen bundles become hyalinized and space between collagen bundles diminish

A

Scleroderma

238
Q

produce increased dermal mucin, mostly hyaluronic acid.

A

Lupus

Dermatomyositis

239
Q

Has autoantibodies directed against type VII collagen

A

Bullous lupus

240
Q

Diseases that have defects in collagen synthsis

A

Ehlers-Danlos syndrome
X-linked Cutis laxa
Osteogenesis imperfecta

241
Q

Defect in elastic tissue

A

Marfan syndrome

Pseudoxanthoma elasticum

242
Q

Dermal vasculature consists of

A

Two intercommunicating plexuses

  1. Subpapillary plexus
  2. Deeper, lower horizontal plexus
243
Q

Upper horizontal network

A

Subpapillary plexus

244
Q

Contains postcapillary venules and courses at the junction of papillary and reticular dermis

A

Subpapillary plexus

245
Q

This plexus furnishes a rich supply of capillaries, end arterioles, and venules to the dermal papillae

A

Subpapillary plexus

246
Q

Vasculature found at the dermal-subq interface composed of larger blood vessels

A

Deeper, lower horizontal plexus

247
Q

Nodular lymphoid infiltrates surroundting this lower plexus are typical of

A

Inflammatory morphea

248
Q

Vasculature of dermis is well developed at sites of

A

Adnexal structures

249
Q

Smooth muscle in the skin occurs as

A

Arrectores pilorum
Tunica dartos of scrotum
Areolas of the nipples

250
Q

Produce goosflesh

Below the sebaceous glands

A

Arrectores pilorum

251
Q

Scattered smoothmuscle throughout the dermis is typical of

A

Anogenital skin

252
Q

Composed of small bundles of smooth muscles that crisscross at right angles

A

Muscularis of veins

253
Q

Smooth muscle forms a concentric, weathlike ring

A

Arterial

254
Q

Specialized aggregates of smooth muscle cells found between arterioles and venules prominent in the digits and lateral margins of palms and soles

A

Glomus bodies

255
Q

Serve to shunt blood and regulate temperature in the digits, lateral margins of palms and soles

A

Glomus bodies

256
Q

Vascular smooth muscle expresses

A

Vimentin

257
Q

Most smooth muscle expresses

A

Desmin inetrmediate filaments

258
Q

This is consistently expressed by all types of smooth muscle

A

Actin

259
Q

Striated msucle occurs in the skin of the neck as

A

Platysma muscle

Face - -muscles of expression

260
Q

Complex network of striated muscle, fascia, aponeuroses

A

Superficial muscular aponeurotic system (SMAS)

261
Q

Presence of long, sausage like granulomas following path of nerves in the deep dermis

A

Hansen’s disease

262
Q

Touch and pressure mediated by

Found in the dermal papillae esp digits, palms and soles

A

Meissner corpuscles

263
Q

Touch and pressure mediated by

On the deeper portion of the dermis of weight-bearing surfaces and genitalia

A

Vater-Pacini corpuscles

264
Q

Temperature, pain and itch are transmitted by these fibers

A

Unmyelinated nerve fibers

265
Q

Temperature, pain and itch pass to the CNS by way of

A

Dorsal root ganglia

266
Q

Histamine-evoked itch is transmitted by

A

Slow-conducting unmyelinated C-polymodal neurons

267
Q

Regulate vasoconstriction, apocrine gland secretions, contraction of arrector pili is regulated by

A

Postganglionic adrenergic fibers

268
Q

Mediate eccrine sweat secretion

A

Cholinergic fibers

269
Q

Play a role in normal immune response in the skin, immediate-type sensitivity, contact allergy, fibrosis

A

Mast cells

270
Q

Resemble fried eggs in histologic sections

A

Mast cells

271
Q

Mast cells become spindle-shaped hyperchromatic, resmble large dark fibroblasts

A

TMeP

Telangiectasia macularis eruptiva perstans

272
Q

Mast cells has receptor site for this Ig

A

IgE

273
Q

Mast cells accumulate in the skin because of abnormal proliferation, migration, and failure of apoptosis

A

Mastocytosis

274
Q

Lobules of fat cells separated by fibrous septa composed of collagen and large BV beneath the dermis

A

Subq

275
Q

Polypeptide that reduces feed intake and weight gain in rodents

A

Obestatin

276
Q

Causes abnormal fat distribution and

Insulin resistance

A

Cushing syndrome

Antiretroviral theraoy

277
Q

Inflammatory dermatoses that affects primaryly the septa or fat lobules

A

Panniculitides

Medicine (29 decks)

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