MBLEX Curriculum-Based Review
ANATOMY & PHYSIOLOGY (11%) Define*
I. Integumentary System - Dermatology
A. Anatomy
1. Skin
a. Epidermis (90% Keratinocytes) – Epithelial Tissue - Ectoderm
i. Stratum corneum *MOST SUPERFICIAL*
ii. Stratum granulosum
iii. Stratum spinosum
iv. Stratum basale * BASEMENT*
+ melanocytes: melanin cells that cause pigmentation in skin
and offer a semi-protective shield against UV radiation.
b. Dermis “TRUE SKIN” (70% Collagen) – Mesoderm
i. Offers structural support to nerve receptors, blood vesicles,
hair follicles, muscles, and glands.
ii. Elastin fibers give skin pliability and resiliency.
iii. Fibroblasts produce collagen fibers that form scar tissue
c. Hypodermis (subcutaneous)
i. Superficial Fascia
ii. Loose connective tissue
+Adipose Tissue + Nerve Receptors + Blood Vessels
iii. Anchors skin to underlying structures
2. Hair
a. Follicle – pouch-like; located in the dermis
b. Shaft – protrudes through a pore in the epidermis
i. Protects Skin & Body Orifices
+Scalp (Injury & UV Radiation) +Eyebrows/Lashes (Debris)
+Nostrils +Ear
ii. Sense of touch
iii. Covers most of the body x/c: palms, soles, lips, nipples,
genitalia
iv. Color = combination of three pigments: brown, yellow & black
c. Arrector Pili – muscles attached to follicles. Contract to pull the hair
upright. “Goosebumps”
3. Nails
a. ANATOMY: compact keratinized cells
i. body – largest and most visible portion
ii. root – production
iii. bed – skin beneath the body
iv. cuticle
+ lunula – crescent-shaped white area at the base of the nail
b. PHYSIOLOGY: protects the distal ends of fingers and toes + tool for
tasks (digging, scratching, and manipulating objects)
4. Glands
a. Sebaceous
1
, i. ANATOMY: sebum (oil) connected to a hair follicle
ii. PHYSIOLOGY: ∙ antibacterial ∙ antifungal ∙ lubricates hair &
epidermis
iii. PATHOLOGY: ∙ Overproduction [ANDROGEN/DISEASE]
∙Underproduction [NUTRITIONAL/ UV Radiation]
b. Sudoriferous
i. ANATOMY: sweat/ perspiration
ii. PHYSIOLOGY: ∙ regulate body temperature ∙ eliminate waste
+Mammary Glands = Modified Sudoriferous Glands
+ Eccrine MOST COMMON x/c lips, ear canal, penis head &
nailbed
+ Apocrine PHEROMONES + HAIR FOLLICLES (axilla & groin)
c. Ceruminous (Specialized Sudoriferous Glands)
i. ANATOMY: cerumen (earwax)
ii. PHYSIOLOGY: traps particles and pathogens as they enter the
ear
B. Physiology
1. Protection
a. Physical Barrier
i. external UV radiation
ii. underlying tissues
2. Immunity
a. Biological Barrier
i. intact skin prevents pathogenic invasion
b. Chemical Barrier
i. skin secretes substances that inhibit pathogenic growth
ii. Dendritic/ Langerhan cells stimulate immune responses when
skin is broken
3. Absorption
a. Fat-soluble molecules
i. oxygen
ii. carbon dioxide
b. Fat-soluble vitamins
i. A
ii. D
iii. E
iv. K
c. Steroids
d. Resins of plants (poison ivy or oak)
e. Salts of heavy metals (lead, mercury and nickel)
4. Sensation (Housing Receptors For):
a. Touch
b. Pressure
c. Temperature
d. Receptors
i. Merkel Disks – light pressure
2
, ii. Nociceptors – Tissue damage: ∙ temperature change ∙ extreme
mechanical stimuli ∙ chemical irritation
iii. Hair Root Plexus – hair movement
iv. Meissner Corpuscles – low-frequency vibrations / textural
sensations
v. Krause Corpuscles – deep pressure, reduced temperature
vi. Ruffini Corpuscles – continuous/persistent touch, skin
stretching
vii. Pacini Corpuscles – high-frequency vibrations / stretches
5. Thermoregulation
a. 98.6° F / 37° C
i. Dilation or Constriction of Blood Vessels
ii. Activity of Sweat Glands
6. Excretion / Elimination
a. Water, Salt, Waste – Sweat
7. Synthesis
a. Vitamin D – nutrient essential for the absorption of calcium
C. Pathologies
1. Skin Color
a. Albinism – Inability to produce melanin
b. Vitiligo – Partial / Total loss of pigmentation
c. Linea Nigra (Pregnancy) – Line between navel and pubic area
d. Melasma (Pregnancy) – Darkening of the skin of face and neck
e. Cyanosis – Blue or purple-tinted skin
2. Contagious/ Infectious
a. Animal Parasites
i. lice
ii. mites
b. Bacterial Infections
i. Boils
ii. Folliculitis
iii. MRSA
iv. Hidradenitis suppurativa
v. Pilondial cysts
vi. Erysipelas (St. Anthony’s Fire)
vii. Necrotizing fasciitis
viii. Impetigo
c. Fungal Infections
i. Tinea capitis
ii. Tinea corporis
iii. Tinea cruris (jock itch)
iv. Tinea pedis (athlete’s foot)
v. Tinea manuum
vi. Onychomycosis
vii. Tinea versicolor
d. Herpes Simplex
3
, i. Oral
ii. Genital
iii. Herpes whitlow
iv. Herpes gladiatorum
v. Herpes sycosis
vi. Eczema herpeticum
vii. Ocular herpes
e. Warts
i. Common
ii. Plantar
iii. Plane
iv. Cystic
v. Filiform
vi. Genital
vii. Butchers’
viii. Focal epithelial hyperplasia
ix. Epidermodysplasia verruciformis
3. Noncontagious Inflammatory Skin Disorders
a. Acne rosacea
i. Erythrotelangiectatic type rosacea
ii. Papulopustular rosacea
iii. Phymatous rosacea
iv. Ocular rosacea
b. Acne vulgaris *MOST COMMON*
c. Eczema
i. Atopic dermatitis
ii. Seborrheic eczema
iii. Dyshidrosis
iv. Nummular eczema
d. Dermatitis
i. Contact
+ IRRITANT
+ ALLERGIC
ii. Stasis
iii. Neuro-
4. Neoplastic Skin Disorders
a. Seborrheic keratosis
b. Skin Cancer
i. Basal Cell Carcinoma (BCC)
+ Nodular
+ Superficial
+Pigmented
+Morpheaform
ii. Squamous Cell Carcinoma (SCC)
+Actinic keratosis
+Actinic cheilitis
4
ANATOMY & PHYSIOLOGY (11%) Define*
I. Integumentary System - Dermatology
A. Anatomy
1. Skin
a. Epidermis (90% Keratinocytes) – Epithelial Tissue - Ectoderm
i. Stratum corneum *MOST SUPERFICIAL*
ii. Stratum granulosum
iii. Stratum spinosum
iv. Stratum basale * BASEMENT*
+ melanocytes: melanin cells that cause pigmentation in skin
and offer a semi-protective shield against UV radiation.
b. Dermis “TRUE SKIN” (70% Collagen) – Mesoderm
i. Offers structural support to nerve receptors, blood vesicles,
hair follicles, muscles, and glands.
ii. Elastin fibers give skin pliability and resiliency.
iii. Fibroblasts produce collagen fibers that form scar tissue
c. Hypodermis (subcutaneous)
i. Superficial Fascia
ii. Loose connective tissue
+Adipose Tissue + Nerve Receptors + Blood Vessels
iii. Anchors skin to underlying structures
2. Hair
a. Follicle – pouch-like; located in the dermis
b. Shaft – protrudes through a pore in the epidermis
i. Protects Skin & Body Orifices
+Scalp (Injury & UV Radiation) +Eyebrows/Lashes (Debris)
+Nostrils +Ear
ii. Sense of touch
iii. Covers most of the body x/c: palms, soles, lips, nipples,
genitalia
iv. Color = combination of three pigments: brown, yellow & black
c. Arrector Pili – muscles attached to follicles. Contract to pull the hair
upright. “Goosebumps”
3. Nails
a. ANATOMY: compact keratinized cells
i. body – largest and most visible portion
ii. root – production
iii. bed – skin beneath the body
iv. cuticle
+ lunula – crescent-shaped white area at the base of the nail
b. PHYSIOLOGY: protects the distal ends of fingers and toes + tool for
tasks (digging, scratching, and manipulating objects)
4. Glands
a. Sebaceous
1
, i. ANATOMY: sebum (oil) connected to a hair follicle
ii. PHYSIOLOGY: ∙ antibacterial ∙ antifungal ∙ lubricates hair &
epidermis
iii. PATHOLOGY: ∙ Overproduction [ANDROGEN/DISEASE]
∙Underproduction [NUTRITIONAL/ UV Radiation]
b. Sudoriferous
i. ANATOMY: sweat/ perspiration
ii. PHYSIOLOGY: ∙ regulate body temperature ∙ eliminate waste
+Mammary Glands = Modified Sudoriferous Glands
+ Eccrine MOST COMMON x/c lips, ear canal, penis head &
nailbed
+ Apocrine PHEROMONES + HAIR FOLLICLES (axilla & groin)
c. Ceruminous (Specialized Sudoriferous Glands)
i. ANATOMY: cerumen (earwax)
ii. PHYSIOLOGY: traps particles and pathogens as they enter the
ear
B. Physiology
1. Protection
a. Physical Barrier
i. external UV radiation
ii. underlying tissues
2. Immunity
a. Biological Barrier
i. intact skin prevents pathogenic invasion
b. Chemical Barrier
i. skin secretes substances that inhibit pathogenic growth
ii. Dendritic/ Langerhan cells stimulate immune responses when
skin is broken
3. Absorption
a. Fat-soluble molecules
i. oxygen
ii. carbon dioxide
b. Fat-soluble vitamins
i. A
ii. D
iii. E
iv. K
c. Steroids
d. Resins of plants (poison ivy or oak)
e. Salts of heavy metals (lead, mercury and nickel)
4. Sensation (Housing Receptors For):
a. Touch
b. Pressure
c. Temperature
d. Receptors
i. Merkel Disks – light pressure
2
, ii. Nociceptors – Tissue damage: ∙ temperature change ∙ extreme
mechanical stimuli ∙ chemical irritation
iii. Hair Root Plexus – hair movement
iv. Meissner Corpuscles – low-frequency vibrations / textural
sensations
v. Krause Corpuscles – deep pressure, reduced temperature
vi. Ruffini Corpuscles – continuous/persistent touch, skin
stretching
vii. Pacini Corpuscles – high-frequency vibrations / stretches
5. Thermoregulation
a. 98.6° F / 37° C
i. Dilation or Constriction of Blood Vessels
ii. Activity of Sweat Glands
6. Excretion / Elimination
a. Water, Salt, Waste – Sweat
7. Synthesis
a. Vitamin D – nutrient essential for the absorption of calcium
C. Pathologies
1. Skin Color
a. Albinism – Inability to produce melanin
b. Vitiligo – Partial / Total loss of pigmentation
c. Linea Nigra (Pregnancy) – Line between navel and pubic area
d. Melasma (Pregnancy) – Darkening of the skin of face and neck
e. Cyanosis – Blue or purple-tinted skin
2. Contagious/ Infectious
a. Animal Parasites
i. lice
ii. mites
b. Bacterial Infections
i. Boils
ii. Folliculitis
iii. MRSA
iv. Hidradenitis suppurativa
v. Pilondial cysts
vi. Erysipelas (St. Anthony’s Fire)
vii. Necrotizing fasciitis
viii. Impetigo
c. Fungal Infections
i. Tinea capitis
ii. Tinea corporis
iii. Tinea cruris (jock itch)
iv. Tinea pedis (athlete’s foot)
v. Tinea manuum
vi. Onychomycosis
vii. Tinea versicolor
d. Herpes Simplex
3
, i. Oral
ii. Genital
iii. Herpes whitlow
iv. Herpes gladiatorum
v. Herpes sycosis
vi. Eczema herpeticum
vii. Ocular herpes
e. Warts
i. Common
ii. Plantar
iii. Plane
iv. Cystic
v. Filiform
vi. Genital
vii. Butchers’
viii. Focal epithelial hyperplasia
ix. Epidermodysplasia verruciformis
3. Noncontagious Inflammatory Skin Disorders
a. Acne rosacea
i. Erythrotelangiectatic type rosacea
ii. Papulopustular rosacea
iii. Phymatous rosacea
iv. Ocular rosacea
b. Acne vulgaris *MOST COMMON*
c. Eczema
i. Atopic dermatitis
ii. Seborrheic eczema
iii. Dyshidrosis
iv. Nummular eczema
d. Dermatitis
i. Contact
+ IRRITANT
+ ALLERGIC
ii. Stasis
iii. Neuro-
4. Neoplastic Skin Disorders
a. Seborrheic keratosis
b. Skin Cancer
i. Basal Cell Carcinoma (BCC)
+ Nodular
+ Superficial
+Pigmented
+Morpheaform
ii. Squamous Cell Carcinoma (SCC)
+Actinic keratosis
+Actinic cheilitis
4
