Why are teeth alive if they’re just bone and can’t regenerate? Why do they need blood flow and are able die?
In: 342
Our bodies are made of living cells and the non-living stuff they make. Matrix is a good word for that non-living stuff.
Different tissues have differences in:
1) the ratio of cells to matrix.
2) what the matrix is made of.
3) the rate at which that matrix is turned over.
1) A tissue like liver or muscle has a very high ratio of cells to matrix. A tissue like a bone or tooth has a relatively low ratio of cells to matrix.
2) Sometimes the matrix is made up of used-to-be living cells. The surface of your skin, your red blood cells, and your platelets are whole or pieces of what used to be living cells. Sometimes it’s mostly protein like the collagen below your skin surface. Sometimes is minerals like in bones or teeth.
3) Some things have to be replaced/repaired very quickly. That includes a lot of the stuff that used to be cells (skin surface, red blood cells, platelets). Other kinds of matrix (especially the mineral ones like teeth and bones) get replaced/repaired much more slowly. But even that slow repair/replacement is performed by living cells within or next to the matrix.
Latest Answers