Tissue Repair

  1. Describe how injuries affect the epithelial, connective, muscular, and nervous tissues

  2. Describe the regeneration process

  3. explain the process of fibrosis

  • Tissues that are incapable of regenerating undergo fibrosis

  • Fibrosis:

    • fibroblasts divide by mitosis and produce collagen to fill in the defect left by injury

    • the tissue does not regain its ability to function normally

    • Thus forming scar tissue, which is dense irregular connective tissue

Capacity for Tissues to Repair

Epithelial Tissue

  • typically capable of full regeneration

  • Skin and digestive tract have some stem cells to replace dead of worn out cells

  • those in the liver and blood vessels divide to replace

Most connective tissue

  • connective tissue proper (bone, and blood) regenerate easily

  • cartilage does not, and will often heal through scar tissue

Smooth muscle tissue and skeletal muscle tissue

  • Smooth heals by regeneration

  • cardiac and skeletal cannot undergo mitosis because of their size and cellular structure

  • Skeletal muscle cells have satellite cells that divide and become muscle cells to aid in regeneration, but cardiac cells do not have that

Nervous tissue

  • Do not regenerate

  • Neuroglial cells have the ability to divide

  • damaged neurons are often replaced by neuroglial cells that divide to make a scar

  • if the cell body of a neuron is intact, and just the axon is damaged, the axon may regenerate, primarily axons outside the brain and spinal cord

Factors Affecting Tissue Repair

  • Tissue repair involves protein production, so protein intake must be adequate

  • Adequate vitamin C is needed as it is required by fibroblasts to make collagen

  • Blood flow is essential as it floods the area with oxygen and nutrients