mbbs ims msu
Upcoming SlideShare
Loading in...5
×
 

mbbs ims msu

on

  • 1,434 views

Epithelial

Epithelial

Statistics

Views

Total Views
1,434
Views on SlideShare
1,434
Embed Views
0

Actions

Likes
0
Downloads
43
Comments
1

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Adobe PDF

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
  • awesomeeeeeeeeee!!!!
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

mbbs ims msu mbbs ims msu Presentation Transcript

  • TISSUES Assoc. Prof. Dr. Karim Al-Jashamy MSU/ IMS 2009
  • Tissue • Groups of cells that share a common structure and function. • In adult organisms, there are four tissue types: • Epithelium tissue • Connective tissue • Muscle tissue • Nervous tissue
  • Epithelium • Epithelial tissues are thin sheets. • Cover body surfaces and organs. • Line body cavities. •Occur at boundaries between two environments.
  • Epithelium • Functions include: • protection • sensory reception • secretion • absorption • ion transport • filtration • formation of slippery surfaces for substance movement.
  • Epithelium Special characteristics of epithelium separate it from the other basic tissue types: • Specialized contacts • Polarity • Support by connective tissue • Avascular but innervated • Regeneration • Cellularity
  • • Classification of Epithelia • • Epithelium is given two names. • • The first name indicates the number of cell layers. • • The second name identifies cell shape. • • Simple epithelium is a single layer of cells. • • Stratified epithelium • has more than one layer.
  • Simple Squamous Epithelium • • Single layer of flat cells. • • Found wherever diffusion or filtration are important. – Capillary linings, alveoli of lungs. • • Endothelium: –Special lining tissue (slippery). –Blood vessels, heart, lymphatic vessels. • • Mesothelium: peritoneal lining tissue – (serosa).
  • Epithelial Tissues • General Features Cellular Layer + Basement Membrane
  • Epithelial Tissues • General Features Cellular Layer + Basement Membrane No Direct Circulation/Blood Supply Touch Each Other Rapid Rate of Cell Reproduction
  • Epithelial Tissues • Structural Classification Cell Shapes
  • Squamous Cuboidal Columnar
  • Epithelial Tissues • Structural Classification Cell Shapes Cell Layers
  • Simple
  • Stratified
  • Epithelial Tissues • Major Types
  • Simple Squamous Epithelium
  • Simple Squamous Epithelium Function: Exchange Sample Locations: Alveoli, capillaries
  • Stratified Squamous Epithelium
  • Stratified Squamous Epithelium Function: Protection Sample Locations: Skin, Mouth, Repro tracts
  • Stratified squamous epithelium (non-keratinized)
  • Simple Cuboidal Epithelium Function: Absorption or Secretion Sample Locations: Kidney, Hormone Glands
  • Simple cuboid epithelium
  • Simple Columnar Epithelium Function: Absorption (or Secretion) Sample Location: Digestive Tract Microvilli
  • Simple columnar epithelium
  • Simple Columnar Note goblet cells
  • Pseudostratified Columnar Epithelium Note cilia
  • Pseudostratified Columnar Epithelium
  • Pseudostratified Columnar Epithelium Function: Absorption, Secretion, Movement Sample Locations: Respiratory & Repro Ducts
  • Pseudostratified epithelium
  • Transitional Epithelium Function: Stretchability Sample Location: Urinary Bladder
  • Transitional epithelium
  • Epithelium cont. • Epithelium that lines cavities sits on lamina propria. – Supports epithelium – Binds epithelium to other tissue – Provides nutrition • Sides of cells are named – Basal – Apical (free) – Lateral
  • Special Features of Epithelial Cells • – Cell junctions are lateral surfaces features that primarily bind adjacent cells to each other. • – Main types: • – tight junction (zonula • occludens) • – adherens junction • (zonula adherens) • – desmosome • – gap junctions
  • Avascular • • Epithelium lacks blood vessels (avascular). • • Epithelium does have some nerve endings that go between cells (innervated).
  • Gap Junction
  • Intercellular Junctions Belts that circle cell. ZO (tight junction) acts as barrier. ZA provides for adhesion of one cell to another Spots Des is like a spot welding. Gap allows passage of chemical for communication.
  • Specializations of Cell Surface • Microvilli – Found mainly on absorptive cells – Brush border, 1m high • Cilia / flagella – Cylindrical, motile structures, 5-10m high – Contain microtubules – Basal bodies
  • Microvilli Apical region of an intestinal epithelial cell seen with TEM. Filaments that constitute the core of the microvilli are clearly seen. An extracellular cell coat (glycocalyx) is bound to the plasmalemma of the microvilli. x45,000.
  • Cilia
  • Regeneration • • Epithelium can regenerate.
  • Glands • • Many epithelial cells make and secrete a product. • • Glands are classed as exocrine (with ducts), or • endocrine (without ducts), as well as – • unicellular – or multicellular. • • One-celled exocrine gland is the goblet cell; its product is mucin • • Endocrine glands secrete hormones.
  • Multicellular Exocrine Glands • • Glands have two parts: – –Secretory portion – –Duct • –Both surrounded by fibrous capsule.
  • Multicellular Exocrine Glands • Simple glands – Unbranched duct • Compound glands – Branched duct – Tubular – Alveolar – Tubuloalveolar
  • Special Features of Epithelial Cells • The basal lamina separates the epithelium and underlying connective tissues. • Apical surface features are microvilli and cilia.
  • Connective Tissue Connective tissue is the most diverse and abundant type of tissue. Cells are separated by extracellular matrix. Four main classes and many subclasses • Connective tissue proper (loose and dense) • Cartilage • Bone tissue • Blood
  • General Features of CT – General structural features: – fibroblast – fibers (collagen, reticular, and elastic) – ground substance – General functional features: – support and binding – holding tissue fluid – fighting infection – storing fat
  • Connective Tissue • Loose areolar connective tissue represents general structural and functional elements of connective tissue. • This CT underlies epithelia and surrounds nerves and vessels. • 3 types of extracellular matrix fibers made by fibroblasts: – Collagen – Reticular – Elastic
  • Connective Tissue • Ground substance: jellylike materials that hold interstitial fluid. – Glysoaminoglycans – Proteoglycans
  • Defense Cells • Areolar CT contains many defense cells. –Macrophages –Plasma cells –Mast cells –Neutrophils, lymphocytes, eosinophils
  • Connective Tissue Classification Connective tissue proper has two subdivisions: Loose connective tissue • Loose connective tissues : • adipose (fat) • reticular (bone marrow)
  • Connective Tissue Classification Dense connective tissue (fibrous connective tissue) Contains more collagen than areolar tissue. • Dense connective tissue: • Regular • Irregular
  • • Connective Tissue Classification • • Other connective tissues: • • Cartilage (supporting rings of trachea) • • Bone (skeleton) • • Blood
  • Covering and Lining Membranes – Covering and lining membranes combine connective and epithelial tissues. – There are three types of covering and lining membranes: • Cutaneous (skin) • Serous (line body cavities) • Mucous (line hollow organs) – Underlying CT is lamina propria
  • Simple Squamous (endothelium)
  • Simple squamous (mesothelium) Lines a body cavity Such as abdominal cavity.
  • References • • Martini. 2002. Fundamental of Anatomy and Physiology. 5th edition. • Prentice Hall International, Inc. • • Norman, F., Gant, F. & Cunningham, G. (1993). Basic Gynecology • and obstetrics. A Lange medical book. Appleton & Lange • • Ganong, W.F. 2005. Review of Medical Physiology, 20th Ed, • Appleton & Lange • • Sherwood, L. 2001. Human Physiology – From Cells to Systems. • 6th edition. McGraw Hill. • • Marieb, E.N. 1998. Human Anatomy and Physiology, 4th Ed, • Addison Wessley Longman Inc, New York. • • Tortora, G.J. dan Grabowski, S.R. 2000. Principles of Anatomy and • Physiology, 9th Ed., John Wiley & Sons, New York