II. Anatomy

  1. Complete Cross Sectional Anatomy
    1. DermSkinAnatomy.jpg
    2. dermSkinXsFullThicknessGrayBB940.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  2. Epidermis
    1. dermEpidermisGrayBB941.gifLewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)

III. Definitions

  1. Epidermis (external skin surface)
    1. Keratinised squamous epithelium
    2. Thickness
      1. Eyelids: 0.05 mm
      2. Palms and soles: 1.5 mm
  2. Dermis (supports Epidermis)
    1. Thick, dense, fibroelastic connective tissue
    2. Highly vascularized
    3. Contains Sensory Receptors
  3. Hypodermis (Subcutaneous layer)
    1. Loose connective tissue with adipose tissue

IV. Physiology: Skin Functions

  1. Sensation (largest sensory organ in the body)
  2. Protection
    1. Prevents Dehydration
    2. Prevents infection
    3. Physical barrier to injury
    4. Protects against ultraviolet light injury (Melanin)
  3. Thermoregulation
    1. Insulation (hair and adipose tissue)
    2. Heat dissipation
      1. Sweat evaporation
      2. Increased Blood Flow
  4. Metabolic
    1. Energy storage of Triglycerides in adipose tissue
    2. Vitamin D synthesis

V. Anatomy: Epidermis Cell Layers (cells mature from inner to outer)

  1. Stratum Corneum (Cornified Layer)
    1. Outermost layer of Epidermis
    2. Composed mostly of keratin (fibrous Protein)
    3. Cells desquamated (27 days after production)
  2. Stratum Lucidum (present only in very thick skin)
  3. Stratum Granulosum (Granular Layer)
    1. Darker layer with intracellular granules
    2. Produces keratin
  4. Stratum Spinosum (Prickle Cell Layer)
    1. Composed of Keratinocytes
    2. Cells produced by basal layer and growing
    3. Keratin production starts
  5. Stratum Germinativum (Stratum Basale, Basal Cell Layer)
    1. Innermost layer of Epidermis
    2. Cells are produced here in the germinal layer
    3. Forms the prickle cells in the layer above

VI. Anatomy: Interspersed cells and units

  1. See Hair Follicle
  2. See Sweat Gland
  3. See Sebaceous Gland
  4. See Melanocyte
  5. Merkel's Cell
  6. Langerhans Cells (in Prickle Layer)
    1. Dendritic histiocytic cells
    2. Intercept Antigenic signal and pass to lymphoid cells
  7. Desmosome (Macula adherens)
    1. Intercellular bridge that attaches epidermal cells
    2. Small dense Plaque with protruding tonofilaments

VII. References

  1. Habif (1996) Clinical Dermatology, Mosby, p. 24
  2. Murphy in Cotran (1989) Robbins Pathology, p. 1277-8
  3. Wheater (1987) Functional Histology, p. 130-2

Images: Related links to external sites (from Bing)

Related Studies

Ontology: Dermis (C0011646)

Definition (FMA) Dense irregular connective tissue which consists of a papillary layer and a reticular layer.
Definition (UWDA) Dense irregular connective tissue which consists of a papillary layer and a reticular layer.
Definition (NCI_NCI-GLOSS) The inner layer of the two main layers of the skin. The dermis has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures. It is made up of a thin upper layer called the papillary dermis, and a thick lower layer called the reticular dermis.
Definition (MSH) A layer of vascularized connective tissue underneath the EPIDERMIS. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are SWEAT GLANDS; HAIR FOLLICLES; and SEBACEOUS GLANDS.
Concepts Tissue (T024)
MSH D020405
SnomedCT 53534000
English Corium, dermis structure, corium, dermis, Dermis structure (body structure), Dermis structure, Dermis, Cutis
French Corium, Derme
Swedish Läderhud
Czech corium, škára
Finnish Verinahka
Russian DERMA, KORIUM, ДЕРМА, КОРИУМ
Japanese 真皮
Italian Corium, Derma
Polish Skóra właściwa, Corium
Norwegian Dermis, Corium, Lærhud
Spanish Corion (Dermis), dermis, estructura de la dermis (estructura corporal), estructura de la dermis, Corium, Dermis
Portuguese Cório, Corium, Derme
German Corium, Dermis
Dutch Dermis, Dermis (huid), Huid

Ontology: Desmosome (C0011703)

Definition (GO) A cell-cell junction in which: on the cytoplasmic surface of each interacting plasma membrane is a dense plaque composed of a mixture of intracellular anchor proteins; a bundle of keratin intermediate filaments is attached to the surface of each plaque; transmembrane adhesion proteins of the cadherin family bind to the plaques and interact through their extracellular domains to hold the adjacent membranes together by a Ca2+-dependent mechanism. [GOC:mah, GOC:mtg_muscle, ISBN:0815332181]
Definition (NCI) Desmosomes are intercellular anchoring junctions that anchor intermediate filaments at membrane-associated plaques in adjoining cells. Desmosomes assemble in response to cell-cell contact and raised levels of extracellular calcium. Sensitivity to calcium levels is lost as desmosomes mature.
Definition (MSH) A type of junction that attaches one cell to its neighbor. One of a number of differentiated regions which occur, for example, where the cytoplasmic membranes of adjacent epithelial cells are closely apposed. It consists of a circular region of each membrane together with associated intracellular microfilaments and an intercellular material which may include, for example, mucopolysaccharides. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990; Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Concepts Cell Component (T026)
MSH D003896
SnomedCT 4573009
LNC LP149594-6
English Desmosomes, macula adherens, spot desmosome, Desmosoma, desmosome, desmosomes, Desmosome, Macula adherens, Desmosome (cell structure), Desmosome (body structure), Macula Adherens, Spot Desmosome
French Desmosomes
Swedish Bindkroppar
Czech desmozómy
Finnish Desmosomit
Russian DESMOSOMY, ДЕСМОСОМЫ
Polish Desmosomy, Plamka przylegania
Norwegian Desmosomer
Spanish desmosoma (estructura celular), desmosoma (estructura corporal), desmosoma, mácula adherente, Desmosomas
German Desmosomen
Italian Desmosomi
Dutch Desmosoom, Macula adhaerens
Portuguese Desmossomos

Ontology: Epidermis (C0014520)

Definition (CHV) the outer layer of skin
Definition (NCI_NCI-GLOSS) The outer layer of the two main layers of the skin.
Definition (NCI) The epithelial portion of the skin (cutis). It consists of the following layers: stratum corneum (horny layer), stratum granulosum (granular layer), stratum spinosum (prickle cell layer), and stratum basale (basal cell layer).
Definition (MSH) The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
Concepts Tissue (T024)
MSH D004817
SnomedCT 55988001
LNC LP14303-9
Swedish Överhud
English Epidermal, epidermis, Epidermis structure (body structure), Epidermis structure, Epidermis
Czech epidermis
Finnish Orvaskesi
Russian EPIDERMIS, ЭПИДЕРМИС
Croatian EPIDERMIS
Polish Naskórek
Norwegian Epidermis, Overhud
Spanish epidermis, estructura de la epidermis (estructura corporal), estructura de la epidermis, Epidermis
French Épiderme
German Epidermis
Italian Epidermide
Dutch Epidermis, Opperhuid
Portuguese Epiderme

Ontology: keratinocyte (C0022567)

Definition (NCI) Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell.
Definition (CSP) vertebrate, epidermal cell of ectodermal origin.
Definition (MSH) Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell.
Concepts Cell (T025)
MSH D015603
SnomedCT 74447004
English Keratinocytes, Keratinized cell of epidermis, keratinocytes, Keratinocytes [Chemical/Ingredient], Keratinocyte, Keratinocyte (cell), keratinocyte
French Kératinocyte, Kératinocytes
Swedish Keratinocyter
Czech keratinocyty
Finnish Keratinosyytit
Russian KERATINOTSITY, КЕРАТИНОЦИТЫ
Portuguese Queratinócitos, Ceratinócitos
Croatian KERATINOCITI
Latvian Keratinocīti
Polish Keratynocyty
Norwegian Keratinocytter
Spanish queratinocito (célula), queratinocito, Queratinocitos
German Keratinozyten
Italian Cheratinociti
Dutch Keratinocyt, Keratinocyten

Ontology: Stratum granulosum (C0221923)

Concepts Tissue (T024)
SnomedCT 49874001
Spanish estrato granuloso, estructura del estrato granuloso (estructura corporal), estructura del estrato granuloso, estrato granuloso (estructura corporal)
English granular layer (epidermis), stratum granulosum, Stratum granulosum structure, Stratum granulosum of epidermis, Granular layer of epidermis, Granular Layer, Stratum Granulosum, Stratum granulosum (body structure), Stratum granulosum structure (body structure), Stratum granulosum

Ontology: Stratum Basale (C0221925)

Concepts Tissue (T024)
SnomedCT 62650009
Spanish estrato germinativo, estructura del estrato germinativo (estructura corporal), estructura del estrato germinativo, estrato germinativo (estructura corporal), estrato basal, estrato de células basales
English basal layer (epidermis), Stratum germinativum structure, Basal cell layer of epidermis, Stratum basalis of epidermis, Stratum basale of epidermis, basal cell layer, stratum basale, stratum germinativum, Basal cell layer, Stratum germinativum, Stratum basale, Basal Layer, Rete Malpighii, Stratum Germinativum, Stratum germinativum (body structure), Stratum germinativum structure (body structure), Stratum Basale

Ontology: Subcutaneous Tissue (C0278403)

Definition (MSHCZE) Volná pojivová tkáň nacházející se pod vrstvou ŠKÁRY – podvrstvy KŮŽE. Může obsahovat TUKOVÉ BUŇKY, jejichž množství a velikost se odvíjí a různí podle lokalizace tělesné oblasti a stavu výživy.
Definition (MSH) Loose connective tissue lying under the DERMIS, which binds SKIN loosely to subjacent tissues. It may contain a pad of ADIPOCYTES, which vary in number according to the area of the body and vary in size according to the nutritional state.
Concepts Tissue (T024)
MSH D040521
SnomedCT 71966008
English Hypodermis, Superficial fascia, hypoderm, superficial fascia, subcutaneous tissues, hypodermis, subcutaneous tissue, Fascia, Superficial, Tela Subcutanea, Tissue, Subcutaneous, Tissues, Subcutaneous, Subcutaneous Tissues, Hypoderm, Subcutaneous tissue, Tela subcutanea, Subcutaneous connective tissue, Subcutaneous tissue structure (body structure), Subcutaneous tissue structure, Subcutaneous connective tissue, NOS, Subcutaneous tissue, NOS, Superficial Fascia, Subcutaneous Tissue
French Toile sous-cutanée, Tela subcutanea, Hypoderme, Tissu sous-cutané
Swedish Subkutan vävnad
Czech hypodermis, subkutánní tkáň, fascia superficialis
Finnish Ihonalaiskudos
Russian GIPODERMIS, KLETCHATKA PODKOZHNAIA, PODKOZHNAIA KLETCHATKA, PODKOZHNAIA TKAN', ГИПОДЕРМИС, КЛЕТЧАТКА ПОДКОЖНАЯ, ПОДКОЖНАЯ КЛЕТЧАТКА, ПОДКОЖНАЯ ТКАНЬ
Italian Tela subcutanea, Ipoderma, Fascia superficiale, Tessuto sottocutaneo
Latvian Zemādas audi
Spanish tela subcutanea, Tela Subcutánea, estructura del tejido celular subcutáneo (estructura corporal), estructura del tejido celular subcutáneo, hipodermis, tejido celular subcutáneo, tejido conectivo subcutáneo, tejido conjuntivo subcutáneo, tejido subcutáneo, Fascia Superficial, Hipodermis, Tejido Subcutáneo
Polish Tkanka podskórna
Japanese 組織-皮下, 皮下組織
Norwegian Underhudsvev, Subkutant vev, Subcutis, Hypodermis
Portuguese Tecido Subcutâneo, Hipoderme, Fáscia Superficial, Tela Subcutânea
German Hypoderm, Hypodermis, Subkutis, Unterhautgewebe
Dutch Fascia, oppervlakkige, Hypodermis, Onderhuid, Onderhuids weefsel, Subcutaan weefsel

Ontology: Skin (C1123023)

Definition (FMA) Nonparenchymatous organ that consists of the epidermis, dermis and sets of hair and nails and which surrounds the entire body. Subdivisions of the skin surround various body parts; as a whole, the skin constitutes the external layer of the body. Examples: There is only one skin.
Definition (OMS) Natural covering of the body.
Definition (UWDA) Nonparenchymatous organ that consists of the dermis and epidermis. Subdivisions of the skin surround various body parts; as a whole, the skin constitutes the external layer of the body. Examples: There is only one skin.
Definition (NCI_CDISC) An organ that constitutes the external surface of the body. It consists of the epidermis, dermis, and skin appendages. (NCI)
Definition (NCI) An organ that constitutes the external surface of the body. It consists of the epidermis, dermis, and skin appendages.
Definition (MSH) The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
Definition (CSP) covering of the outer region of the body that protects it from the environment.
Concepts Body System (T022)
MSH D012867
SnomedCT 181606000, 39937001
LNC LP76007-1, LP36760-4, LP130014-6, MTHU001414, LA4332-8
English Skin, Skin NOS, cutaneous tissue, Skin of body, Cutis, skin system, skinned, skins, skin, skin structure, integumental system, integument, Skin NOS (body structure), Piel, SKIN, Integumental system, Skin structure (body structure), Skin structure, Skin, NOS, Skin (Anatomy), Integument
Swedish Hud
Czech kůže
Finnish Iho
Russian KOZHA, КОЖА
Croatian KOŽA
Polish Skóra
Norwegian Hud
Spanish piel, SAI (estructura corporal), piel, SAI, estructura de la piel (estructura corporal), estructura de la piel, piel, Piel
French Peau
German Haut
Italian Pelle
Dutch Huid
Portuguese Pele

Ontology: Intraepidermal Route of Drug Administration (C1512941)

Definition (HL7V3.0) <p>Intraepidermal</p>
Definition (HL7V3.0) <p>Intraepidermal</p>
Definition (NCI_CDISC) Administration within the epidermis. (FDA)
Definition (NCI) Administration of a drug within the superficial epithelial layer of the skin.
Concepts Functional Concept (T169)
HL7 _IntraepidermalRoute, 2.16.840.1.113883.1.11.17135
English IntraepidermalRoute, Intraepidermal Route of Administration, Intraepidermal, Intraepidermal Route of Drug Administration, INTRAEPIDERMAL, I-EPIDERM