Regenerative capacity is the ability of an organism to regrow certain parts of the body, and it varies from species to species.
Species such as salamanders and newts have an enhanced capacity to regenerate because they retain significant clusters of stem cells within their bodies. When regeneration is required, these stem cells can migrate to the necessary part of the body to initiate regrowth. Regeneration is of two types:
- Complete regeneration is when the lost or damaged tissues are replaced with identical tissues.
- Incomplete regeneration is when the newly formed tissue is not identical in structure or function to the tissue that has been injured or lost.
Humans typically exhibit incomplete regeneration in response to injury, and it varies by the tissue type. Liver tissue has a high regenerative capacity, often able to undergo extensive regeneration following injury or loss. Unfortunately, the heart has little, if any, regenerative capacity, and scarring often results following an injury such as a heart attack. The kidneys have moderate regenerative capacity and can repair nephrons after damage to the tubules; however, this regenerative capacity is easily overwhelmed, and kidney failure may result.
Key Points
• When the lost or damaged tissues are replaced with identical tissues, it is complete regeneration.
• When the newly formed tissue is not identical in structure or function to the tissue that has been injured or lost, it is said to be incomplete regeneration.
• Humans exhibit incomplete regeneration in response to injury.
• Other species have an enhanced capacity to regenerate because they retain significant clusters of stem cells within their bodies.
Key Terms
regeneration: is the process of renewal, restoration, and growth
complete regeneration: when the lost or damaged tissues are replaced with identical tissues.
incomplete regeneration: when the newly formed tissue is not identical in structure or function to the tissue that has been injured or lost.