Regeneration Flashcards
What is regeneration?
Natural renewal of dead/damaged tissue that happens through the proliferation of cells in the surviving parts of the tissue. The damaged tissue will be replaced by the same type of tissue.
What types of tissues regenerate well?
-Epithelium (esp. epidermis)
-Fibrous connective tissue (not other types of connective)
What types of tissues do not regenerate well?
-Muscles
-Nerve tissue
-Cardiac muscle
What does intracellular regeneration mean?
Happens in cells that don’t divide (cardiac muscle, brain). The cell’s ultrastructure is replaced by new elements (cytoplasm organoids).
What are the three types of regeneration?
Physiological
Reparative
Pathological
What is physiological regeneration?
Natural physiological progress. The normal, continuous process of cells dying and being replaced by new cells.
Lizards can also regenerate their broken tail.
When does reparative regeneration take place?
Takes place when cells/tissues are damaged by a pathological process.
What types of reparative regeneration are there?
-Full regeneration: regenerated tissue is identical to the damaged tissue
-Incomplete regeneraion: New tissue differs from the original tissue
-Substitution: more frequent progress of regeneration
What happens in case of incomplete regeneration?
Defect is filled with connective tissue –> scar formation
Loss of functionality could be compensated by hypertrophy of the healthy part of the organ.
What affects the process of regeneration?
Exogenic and endogenic factors
Relevant factors: age, diet, nerve and humoral processes, medical care
What does hyporegenerative mean?
Progress is slow, the regenerate (new tissue) us weak or missing
What does hyperregenerative mean?
Excessive formation of the regenerate, e.g. extra flesh of skin
