Question: Can a DNA strand die and if so how?

Reka Nagy answered on 8 Jan 2019:

DNA itself is not alive as such – but while it is inside the cell, it can sustain itself and copy itself using the machinery present in the cell. However, if DNA is removed from the cell, it will lose access to all this machinery and by itself, will become inert – unable to do anything. If it is exposed to somewhat harsh conditions (or if it is like this for a long period of time), it will start to deteriorate, since it is made of organic molecules that, like any other chemicals, will undergo spontaneous changes.

Interestingly, however, we are able to recover DNA from ancient bones, for example, because the bones offer some protection to the DNA so it is not exposed to the environment, which is why we are able to sequence the genomes of ancient samples! So all things considered, DNA can be pretty hardy!