Summary of Junqueira: Histology of the Skin with additional material from Netter's, DeFiore's and Weiss' Atlases. Includes abridged but detailed explanation of key point with Electron Microscopy, H&E, Immunohistochemistry and Diagrams.
02 connective tissue histology notes to 31 slides / images Class notes MTY1204 (histology) Junqueira's Basic Histology: Text and Atlas, Fiifteenth Edition, ISBN: 9781260026177
05 bone histology 39 notes to slides / images Class notes MTY1204 (histology) Junqueira's Basic Histology: Text and Atlas, Fiifteenth Edition, ISBN: 9781260026177
Immune System & Lymphoid Organs
Alles voor dit studieboek
(16)
Geschreven voor
David Tvildiani Medical University
Histology
Alle documenten voor dit vak (7)
2
beoordelingen
Door: christinathomas • 1 jaar geleden
Door: michelatornincasa • 4 jaar geleden
Verkoper
Volgen
galadashvili
Ontvangen beoordelingen
Voorbeeld van de inhoud
• Skin is the largest organ of the human body accounting for 15 to 20% of total body
weight.
• Also known as INTEGUMENT or CUTANEOUS LAYER, it is composed of:
◦ Epidermis- Epithelial cells
derived from Ectoderm. Which gives
rise to
‣ Hair
‣ Nails
‣ Sebaceous and Sweat Glands
◦ Dermis- Cells derived from
Mesoderm
◦ Dermal Papillae- between the two
laters. containing epidermal
ridges which strengthen the bond
between the two layers.
• Beneath the Dermis there is the
SUBCUTANEOUS TISSUE or HYPODERMIS
which is loose connective tissue
containing PADS OF ADIPOCYTES. It
Binds Skin to underlying tissues
producing the Superficial Fascia.
Ep- Epidermis
De- Dermis
BV- blood vessels
PC- Pacinian Corpuscules
SG- sweat glands
The Functions of Skin:
Protection
• Physical and Chemical Barrier that provides defense against
◦ Microbes
◦ Friction
◦ Suns UV rays
Sensory
• Various sensory receptors allow body to monitor the environment and regulate body's
interactions with physical objects
Thermoregulatory
• Keeps body's temperature in homeostasis by insulating substances such as hair and
adipose deposits by accelerating heat loss through sweating
Metabolic
• Synthesizes Vitamin D3
• Removes excess electrolytes through sweat
•Stores Energy as Fat
Sexual Signaling
• Visual indictor of health(hair, complexion) which is involved in attraction
• Sex pheromones produced by apocrine glands are excreted through sweat
Dermatoglyphs or fingerprints are interdigitations/sulci between dermis and
epidermis, which form an unique pattern of loops, arches and whorls for each
individual.
• Skin is Elastic and can stretch to accommodate swollen areas
• Self Renewing and Rapidly repairable
, EPIDERMIS:
• Consists of Stratified Squamous Keratinized Epithelia
composed of:
a. Keratinocytes
b. Melanocytes- pigment cells
c. Langerhans Cells- antigen presenting macrophages
d. Merkel Cells- tactile epithelial cells
• Epidermis is AVASCULAR, it receives its nourishment by
diffusion through Dermis.
• Thick Epidermis 400 to 14000μm(1.4mm) on palms and soles
• Thin Epidermis 75 to 150μm
Epidermis Consists of 4 layers or Strata of Keratinocytes:
• Basal Layer or Stratum Basale or Stratum Germinativum
◦ Single Layer of tightly packed Basophilic cuboidal or
columnar epithelial cells knows as Keratinocytes
◦ Keratinocytes are attacked to Basal membrane/lamina
by Hemidesmosomes and are attached to each other by
Desmosomes
◦ Keratinocytes have Oval Nuclei that show Intense
Mitotic Activity containing progenitor cells for
other Epidermal layers
◦ Contains Keratins which are 10nm dimeter Intermediate
Filaments
◦ Melanocytes and Merkel Cells are also found
• Spinous Layer or Stratum Spinosum
◦ The thickest layer
◦ Polyhedral Cells with prominent Nuclei and Nucleoli
that become flatter as they approach the surface.
◦ Active Cytoplasms synthesizing Keratins
◦ Keratin fibers are assembled into
Tonofibrils that converge and terminate on
desmosomes holding the cell layers together
◦ Langerhans Cells are found here
The Basal and Spinous layers together are called
STRATUM GERMINATIVUM or The Malphigian Layer
• Granular Layer or Stratum Granulosum
◦ Composed of THREE to FIVE layers of
flattened cells
◦ Cells undergo terminal differentiation of
KERATINIZATION
◦ Basophilic Keratohyline Granules fill the
Circle- Desmosome
cytoplasm Arrow- Hemidesmosome
◦ Dense Non-membrane bound masses of
FILAGGRIN, associated with
Tonofibrils
◦ Golgi-derived LAMMELAR
GRANULES, which are composed of
various glycolipids are
exocytosed and produce a lipid
rich membrane around the cell
which serves to: Prevent water
loss Physical Barrier
• Pale Layer or Stratum Lucidum
◦ Translucent slightly
eosinophilic layer
◦ Only found in Thick Skin with a
lot of cytoplasmic Keratin
Filaments
◦ Tightly packed squamous cells
that contain no nuclei or
organelles
• Corneal Layer ot Stratum Corneum
◦ 15 to 20 layer of Squamous
Keratinized Cells or SQUAMES
which are flat and Anucleated
‣ Keratin Replaces the cytoplasm in these cells
◦ Shed continuously and protects against FRICTION and WATER LOSS- Desquamation
Voordelen van het kopen van samenvattingen bij Stuvia op een rij:
Verzekerd van kwaliteit door reviews
Stuvia-klanten hebben meer dan 700.000 samenvattingen beoordeeld. Zo weet je zeker dat je de beste documenten koopt!
Snel en makkelijk kopen
Je betaalt supersnel en eenmalig met iDeal, creditcard of Stuvia-tegoed voor de samenvatting. Zonder lidmaatschap.
Focus op de essentie
Samenvattingen worden geschreven voor en door anderen. Daarom zijn de samenvattingen altijd betrouwbaar en actueel. Zo kom je snel tot de kern!
Veelgestelde vragen
Wat krijg ik als ik dit document koop?
Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.
Tevredenheidsgarantie: hoe werkt dat?
Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.
Van wie koop ik deze samenvatting?
Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper galadashvili. Stuvia faciliteert de betaling aan de verkoper.
Zit ik meteen vast aan een abonnement?
Nee, je koopt alleen deze samenvatting voor €2,94. Je zit daarna nergens aan vast.
