Chapter 5 - Tissue Organization PDF

Chapter 5 - Tissue Organization Introduction:  Tissue = group of cells similar in structure and function and their extracellular material that perform a common function  Histology  Pathology  Four basic tissue types...

Chapter 5 - Tissue Organization Introduction:  Tissue = group of cells similar in structure and function and their extracellular material that perform a common function  Histology  Pathology  Four basic tissue types 1 What are the four basic types of tissue?  Tissue = cells + ECM (fibers & ground substance) 1. Epithelial 2. Connective 3. Muscle 4. Nerve  “Con-MEN” 2  What is a cell  Point of contact between adjacent membranes Varied functions: junction?   Fluid-tight seals between cells (Ch 4 pg134)  Anchor cells together or to extracellular material  Channels  Types of junctions:  Tight, Adherens, Desmosome, Hemidesmosome & Gap 3  Tight Junctions  Impermeable barrier between cells  Transmembrane proteins fuse plasma membranes 4 Adherens Junctions  Adhere cells together so tissues can stretch  Structural components  plaque  microfilaments  integral mb proteins (cadherins) 5  Desmosomes  Resist cellular separation & cell disruption  Similar structure to adherens  Plaque & cadherins 6 Hemidesmosomes  Half a desmosome  Connect cells to basement membrane  Integrins  Attach to laminin  Attach to keratin 7  Gap Junctions  Connection between neighboring cells via connexons  Forms protein channel  Functions:  Communication  Transport 8  Describe the general features of epithelial tissues: 1. Cellularity: Closely packed cells  form continuous sheets 2. Polarity: apical vs basal surface 3. Attached to basement membrane (BM) 4. Avascular but 5. good nerve supply (Innervation) 6. Regenerative capacity high: Rapid cell division 9  General Features of Epithelial Cells  Surfaces of epithelial cells differ in structure:  Apical (free) surface  Lateral surfaces  Basal surface  Cells sit on basement membrane  Basal lamina  Reticular lamina  Functions  What are the two different types of epithelium? 1. Covering & lining  epidermis of skin  lining of blood vessels, ducts & body cavities  lining respiratory, reproductive, urinary & GI tract 2. Glandular epithelium  secreting portion of glands  thyroid, adrenal & sweat glands  Functions  protection, filtration, lubrication, secretion, digestion, absorption, transportation, excretion, sensory reception, and reproduction 11 How is epithelial tissue classified?  Arrangement of cells into layers  simple  stratified  pseudostratified  Shape of surface cell  squamous  cuboidal  columnar  transitional Summary of Types of Epithelial Tissue 13 Simple Squamous Epithelium 14  Stratified Squamous Epithelium 15 Clinical Application: Pap Smear  What is a Pap test?  Checks for changes in cervical cells - Infection (HPV) http://www.4woman.gov/faq/pap.htm#pap01 - Abnormal cells http://en.wikipedia.org/wiki/Image:Cervical_AIS,_ThinPrep.jpg - Cervical cancer  Do all women need Pap tests?  How often? 16 Simple Cuboidal Epithelium 17 Stratified Cuboidal Epithelium 18 Non-ciliated Simple Columnar Epithelium 19 Ciliated Simple Columnar Epithelium 20 Stratified Columnar Epithelium 21 Pseudostratified Ciliated Columnar Epithelium 22 Transitional Epithelium 23  Concept Maps are a great study tool for tissues – create your own! 24 Glandular Epithelium: Endocrine  Derived from epithelial cells  Endocrine glands  Secrete hormones into bloodstream 25  Glandular Epithelium: Exocrine  Derived from epithelial cells  Exocrine glands  Secrete onto free surface of epithelial layer  Connected to surface by ducts  Goblet cell  Some glands both endocrine & exocrine in activity 26 Structure of Exocrine Glands 27 Methods of Exocrine Gland Secretion 28  What is connective tissue?  Cells separated by extracellular matrix (ECM = protein fibers and ground substance)  What are the functions of connective tissue? - binding - support - protection - form blood - store fats - fill spaces 29  What are the three fibers types in CT? 1. Collagen fibers 2. Elastic fibers 3. Reticular fibers 30  Clinical Application: Marfan Syndrome  Inherited disorder of fibrillin gene  Abnormal development of elastic fibers  Tendency to be tall with very long legs, arms, fingers & toes, pectus excavatum  Life-threatening weakening of aorta may lead to rupture 31  Ground Substance  May be viscous liquid, semisolid gelatinous, or solid  Supports cells & fibers, binds cells  Glycoaminoglycans (GAGs)  Polysaccharide that attracts cations & water, Ex.s Chondroitin sulfate, Hyaluronic acid  Proteogylcan (GAG + small protein)  Spread out (charges repel each other)  Glycoprotiens (protein + small carb.)  Glue to bind fibers, cells, etc., Ex.s Laminin, fibrillin 32  What Types of Cells Hematopoeisis Bone Marrow stroma Are In Leukocytes/WBCs  Blood CT?  Resident Cells  Wandering cells  Mesenchymal cells  Mast cells  Fibroblast  Free macrophages  Chondroblast/Chondrocyte  Leukocytes (WBCs)  Osteoblast/ Osteocyte  Adipocytes  Fixed Macrophages 33 Connective Tissue Development 34  Connective Tissue Classification 35  Describe the general features of connective tissue:  Highly vascular  Immature cells ends w/ blast (Ex: Fibroblast)  Cyte cells = Differentiated fibroblasts  Derived from mesoderm  mesenchyme  Mucous (Wharton’s Jelly) 36  Connective Tissue  Types of cells present vary according to type of tissue  Each has unique characteristics  Ground substance  Determines consistency of matrix  Supports cells & fibers, binds cells 37  Connective Tissue 1. Loose connective  areolar  adipose  reticular 2. Dense connective 3. Cartilage 4. Bone 5. Blood http://www.udel.edu/Biology/Wags/histopage/colorpage/cct/cct.htm 6. Lymph  Loose Connective Tissue: Loose Areolar CT  Most widely distributed in the body  Contains several types of cells & all three fibers 39 Loose Connective Tissue: Adipose  Contains adipocytes  Insulation & energy reserves  White (common) & brown adipose tissue 40 Loose Connective Tissue: Reticular CT  Interlacing reticular fibers and cells  Forms the stroma of liver, spleen, & lymph nodes 41  Dense Connective Tissue  More fibers but fewer cells  Fibroblast  Types of dense connective tissue:  dense regular  dense irregular  elastic 42 Dense Regular Connective Tissue  Bundles of collagen fibers are regularly arranged in parallel patterns for strength  Tendons & most ligaments 43 Dense Irregular Connective Tissue  Collagen fibers are usually irregularly arranged  Found where pulling forces are exerted in many directions Dense Elastic Connective Tissue  Contain branching elastic fibers  Strong - can recoil to original shape after stretching  Cartilage  Dense network of collagen fibers & elastic fibers embedded in chondroitin sulfate  Strength & resilience  Chondrocytes - lacuna  Avascular  Types of cartilage:  hyaline cartilage  fibrocartilage  elastic cartilage 46  Hyaline Cartilage  Most abundant cartilage in the body  Surrounded by perichondrium (some exceptions like articular cartilage)  Functions  Provide flexibility & support  Reduces friction 47  Fibrocartilage  Chondrocytes scattered among collagen fibers within ECM  Lack perchondrium  Strongest type of cartilage 48  Elastic Cartilage  Chrondrocytes are located within a threadlike network of elastic fibers  Pericondrium is present  Provides strength & elasticity 49  Growth & Repair of Cartilage  Grows and repairs slowly because it is avascular  Interstitial growth  chondrocytes divide and form new matrix  occurs in childhood and adolescence  Appositional growth  chondroblasts secrete matrix onto surface  produces increase in width 50   Calcium salts in matrix w/ collagen fibers  Osteocytes in lacuna Bone  Fxns (Osseous)  Hematopoiesis Tissue  Two types of bone:  Dense bone – Haversion system (osteon)  Spongy bone – Trabeculae 51  Compact Bone  Osteon (Haversian system)  Lamellae  Osteocytes  Canaliculi  Central canal 52  Spongy Bone  Trabeculae  No osteons 53 Liquid Connective Tissue  Blood  Liquid matrix = plasma  Erythrocytes, leukocytes & platelets  Fxn = transport  Lymph  Interstitial fluid flowing in lymph vessels  Contains less protein than plasma  Move cells & substances (eg., lipids) from one part of the body to another 54 Integration of Tissues In Organs 55 Integration of Tissues In Organs 56  Membranes  Epithelia sitting on thin layer of connective tissue  Epithelial tissue mb  mucous mb  serous mb  cutaneous mb (skin)  Connective tissue mb - synovial mb 57  Muscle  Motion, posture & heat production (thermogenesis)  Types of muscle: 1. skeletal 2. cardiac 3. smooth 58  Skeletal Muscle  Attached to bones of the skeleton  Striated  Voluntary movement or contractions by conscious control  Cylindrical 59  Cardiac Muscle  Striated  Involuntary movement or contraction not consciously controlled  Intercalated disc 60  Smooth Muscle  Walls of hollow internal structures  Blood vessels, airways of lungs, stomach, & intestines  Non-striated  Usually involuntary control 61  Functions Basic Tissue -  Conduct electrical signals  Detect changes inside & Nervous outside body  Respond to stimuli  Two main cell types: 1. Neurons 2. Glial cells 62  Pyramidal Neurons from the Central Nervous System Copyright Dennis Kunkel at www.DennisKunkel.com http://www.meddean.luc.edu/lumen/MedEd/Histo/HistoImages/hl3-03.jpg. 63  Tissue Modification  Hypertrophy  Atrophy  Hyperplasia  Metaplasia  Dysplasia  Neoplasia 64  Metaplasia, Dysplasia, & Hyperplasia can lead to…  Neoplasia (cancer) 65  Tissue Trauma  Causes inflammation, characterized by:  Dilation of blood vessels  Increase in vessel permeability  Redness, heat, swelling & pain http://www.emedicine.com/oph/topic219.htm 66 Tissue Repair: Restoring Homeostasis  Worn-out, damaged tissue must be replaced (mitosis)  Some cell types can divide (liver & endothelium)  contain stem cells  some cell types can not divide & are not replaced (neurons)  Stromal vs. Parenchymal cells  Fibrosis vs. Regeneration 67 Stem Cells 68  Conditions Affecting Tissue Repair  Nutrition  Proper blood circulation  Aging 69 Name this tissue Hyaline cartilage 70 Name this tissue Dense irregular connective tissue 71  Identify this tissue  Simple columnar epithelium 72  Identify this tissue  Compact bone 73  Identify this tissue  Smooth muscle tissue 74  Identify this tissue  Blood 75 Name this tissue Reticular connective tissue 76  Identify this tissue  Simple cuboidal epithelium 77 Identify this tissue  Simple squamous epithelium 78  Identify this tissue  Pseudostratified columnar epithelium 79  Identify this tissue  Transitional stratified epithelium of bladder 80 Identify these tissues Dense fibrous connective 81  Identify this tissue  Skeletal muscle 82  Identify this tissue  Stratified squamous 83 Identify this tissue  Simple squamous epithelium 84  Identify this tissue  Stratified cuboidal epithelium 85  Identify this tissue  Stratified keratinized squamous epithelium 86  Identify this tissue  Adipose 87  Identify this tissue  Pseudostratified ciliated columnar epithelium 88