Is it always scar tissue and it just blends in better or does the body sometimes grow skin?
In: Biology
On top of what other people have said, it also has to do with the gene expression patterns of cells in the tissue. When our skin is formed, stem cells are able to divide and differentiate into many cell lines and that gives the skin its appearance and functionality. As we develop and age, those stem cells are gone and we are not able anymore to just make more skin. Scar tissue is made of “dumber” cells that can do the job of keeping the integrity of the skin and not much more.
Plants are a very good example of how sometimes scar tissue is the answer, and sometimes new tissue. If you nick in the stem, scar tissue will appear, but if a root is broken, the plant is able to produce a new root. Plants are awesome.
Also some types of cancer/tumors are basically cells that behave like stem cells, generating new tissue and differentiated cells but in an erratic way. Check out “teratome” in google Images if you want to see a blob with hair and teeth. xD
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