Tissue Repair Pages 100 101 Methods of Tissue

Tissue Repair Pages 100 -101

Methods of Tissue Repair q Two methods: q Regeneration (Replacement) qdestroyed tissue is replaced by the same kind of cells; q Mitosis: cells divide to make new ones q Fibrosis (Repair) qdense (fibrous) connective tissue (scar tissue) replaces the original tissue q Method is determined by: q Type of tissue damaged q Severity of the injury © 2015 Pearson Education, Inc.

Events in Tissue Repair Inflammation ◦ Capillaries become very permeable ◦ Clotting proteins migrate into the area ◦ A clot (visible fibers from blood) walls off the injured area Granulation tissue forms ◦ Growth of new capillaries ◦ Rebuild of collagen fibers to form a bridge Surface epithelium grows underneath © 2015 Pearson Education, Inc.

Tissue Repair = SCAR TISSUE The severity of the wound determines the extent of scarring Scar tissue: ◦ ◦ ◦ Many collagen fibers Lacking blood supply Very strong No flexibility or elasticity Loss of normal function of original tissue © 2015 Pearson Education, Inc.

Tissues that: regenerate easily/well ◦ Epithelial tissue (skin and mucous membranes) ◦ Fibrous connective tissues and bone regenerate poorly ◦ Skeletal muscle ◦ Dense connective tissues: tendons, ligaments Are replaced largely with scar tissue ◦ Cardiac muscle ◦ Nervous tissue within the brain and spinal cord © 2015 Pearson Education, Inc.