Connective Tissue

Connective Tissue

1. Group of tissues that maintain the form of the body and its organs

   • Provides cohesion and internal support

2. Vary in Density, Cellularity, Being specialised

3. Divisions of connective tissue

   • Loose connective tissue
     • Loosely arranged cells and fibres in semi fluid substance
       • Support tissues and organs from strain and displacement
         • Areolar tissue
           • Beneath skin- support framework for epithelium
             • Macrophages, fibroblasts and mast cells
               • Many collagen and few elastic fibres
             • Holds organs in place
           • Serves as a reservoir for salts and water for surrounding tissues
             • Under the skin
               • Between muscles
                 • Supporting blood vessels and nerves
                   • Dental pulp
     • Adipose Tissue
       • Present beneath the skin
       • Store fat
       • Large storing capacity
       • White adipose tissue
         • Support Kidneys
           • Thermal insulator
       • Brown adipose tissue
         • Walls of large blood vessels
           • Maintain body temp
       • Protective cushion around organs
       • Reservoir to store fat soluble vitamins
       • Love handles
   • Dense connective tissue
     • Collagen fibres in bundles- regularly or irregularly between cells
     • Dense regular
       • Tendons muscles to bone and ligaments- bone to bone
     • Dense irregular
       • Skin has fibroblasts and many fibres where tension is required in different directions
   • Specialised connective tissue
     • Cartilage
       • Hyaline
       • Elastic
       • Fibrous
       • Calcified
     • Bones
       • Hard skeletal tissue- composed of cells, fibres and matrix
     • Blood
       • Highly specialised fluid consisting of plasma, erythrocytes, leucocytes and platelets
   • Disorders
     • Ehlers Danlos
     • Marfans syndrome

4. Building blocks

   • Fibroblasts
     • Irregular process
     • Large, flat cells
     • Produce collagen and elastic
     • Tissue repair where they bind together and form granulation tissue
   • Blood cells
   • Macrophages
     • Irregular shaped
     • Granules in cytoplasm
     • Phagocytic cells of connective tissue
       • Actively assist defence systems
     • Monocytes in blood stream specialise as macrophages
   • Lypmhocytes
     • White blood cell
     • Specialised immune cell
     • B-cells and T-cells
     • Formation of antibodies
   • Eosinophils
   • Mast cells
     • Large cytoplasmic granules
     • Liver and spleen
     • Produce and release heparin, serotonin and histamine
       • When damaged by disease or injury
   • Adipocytes and Melanocytes
     • Singly or in groups in adipose tissue
       • Vary in size and shape depending on the amount of fat they contain
         • Many locations
     • Responsible for pigmentation and contain melanin

5. Fibres of connective tissue

   • Produced by fibroblasts
   • Reticular
     • Made of collagen protein- Reticulin
     • Form criss crosses of delicate fibres
   • Collagen
     • Most prevalent fibres
     • Resist stress and impart strength
   • Elastic
     • Readily stretched
     • Impart elasticity to the tissue

6. Ground substance

   • Non-cellular substrate
   • Amorphous material that forms jelly like matrix- Keeps fibres together
   • Can exist as both liquid and gel