CBH CONNECTIVE TISSUE 20

• Types of connective tissue

  Connective tissue proper , Adipose , cartilage , bone
• Functions

  Physically supports and connects other tissuesmaintains the water required for metabolites diffusion to and from the cellscontains blood vessels and nervescontains cells responsible for inflammatory and immune responses
• Composition

  Cells Extracellular matrix
• Connective tissue proper CELLS

  Cells: fibroblasts, mesenchymal cells, adipocytes other cells: macrophages, mast cells, plasma cells, leukocytes
• Connective tissue proper extracellular matrix

  Fibres: collagen, reticular and elastic Ground substance. Glycosaminoglycans, proteoglycans and glycoproteins

  
• Fibroblasts


  Most common type in CT proper spindle-shaped or stellated cells, with thin processes synthesize the components of the ECM

  
• Mesenchymal cells


  Main cells of the mesenchyme (primitive CT in embryo)synthesize the components of the ECMSome remain in adultsaround vessels = perivascular cells
• Adipocytes

  Specialized in synthesizing and storing lipids diameter 25 to 2000 micrometers some appear in loose CT
• Macrophages

  Specialized in phagocytosis of foreign particles, within the defense/cleansing system of the organism
• Location of macrophages

  Mucous membranes Langerhans cells of the skin . Kupfer cells in the liver ,spleen, lymph nodes and bone marrow osteoclasts in bone , microglia in the nervous system
• Mast cells


  Cytoplasm full of granules heparin, histamine, and chemotactic is present in granules they activate allergic reactions

  
• Plasma cells


  Oval cells present diffuse basophilia synthesise and secrete antibodies Originate from B lymphocytes mainly in lamina propria of the digestive tract

  
• Inflammation


  Destroy the damaging agent limiting tissue injury regeneration or healing
• Collagen fibres


  Most abundant form networks and give strength and flexibility
• Types of collagen

  28 typesclassical collagen: fibrillar collagens i,ii,iii network collagens iv in basal laminae
• Basement membrane and basal lamina


  Specialized EMC layer under the basal surface of epithelia as well as around some cell types

  
• Reticular fibres

  Found in very delicate tissues of many organsconsists mainly of type II collagen located in the stroma of bone marrow, lymphoid organs, around adipocytes, glands, and muscle cells

  
• Elastic Fibres


  Main property: elasticity are abundant in airways, elastic arteries and some ligaments
• Ground substance


  The watery, largely unstained extracellular material that fills the space between cells and fibres in CT
• Composition of ground substance

  Glycosaminoglycans: hyaluronan, chondroitin sulfate, keratan sulfate Proteoglycans: attached to a core proteinMulti-adhesive glycoproteins: fibronectin and lamin