Nuclear dna can be extracted from bones and teeth to determine personal identification. if, however, the nuclear dna is degraded or damaged, there is another substance which is more plentiful and durable that can be analyzed. what is the name of this substance?

The name of the other substance that  is more plentiful and durable that can be analyzed is the mitochondrial DNA.  Nuclear DNA is located within the nucleus of eukaryotes cells and usually have two copies per cell, while mitochondria DNA is located in the mitochondria, which are organelles that convert energy from food into a form that cells can use.