What are the living characteristics of a virus?

The debate of whether or not viruses are alive was historically one of difficulty. Today, however, it is generally accepted that they are not living creatures (for a reason which I will explain later).

From the qualities you have listed, they are capable of reproduction, can change over time and are based on a universal genetic code (one that may be even more archaic than our own, actually, in some cases). Interestingly enough, some do indeed respond to their environment - a particular group of viruses has the ability to choose whether to hide in the genome of an organism if it the cell it is in is healthy, and reproduce without doing any work at all simply as the host's cells divide (i.e. - the host replicates the genome, with the virus embedded, and sends it to a new cell - the new cell is born infected), or to lyse the cell and spread via infection, if the cell is deemed to be unhealthy.

In spite of this, the major selling point was that they are not capable of reproduction, except without a host. It was decided that, among almost every other property of all living things, the ability to survive and reproduce individual of other factors was paramount.

I hope this helps. =]

2

Either answer is correct, you just have to provide arguments for whichever side you choose. You could argue that viruses are not living because they can't reproduce on their own. They require the cellular machinery of another organism to reproduce. You can argue that they are living because they contain genetic material (DNA or RNA), and they reproduce.