A major argument in Biology

While being in the class my professors were giving their lecture on Viruses. It was brought up in class whether viruses are alive or simply a strand of DNA inside a protein shell that wanders around on the cellular level. Viruses infect health cells but injecting their DNA into the host cell. The DNA is either going to make the cell make copies of the virus then destroy the cell or live within the cell until it decides to force the cell to make its copies. Biologists continue to argue their views on the matter even now, it has yet to be answered. You can look at the virus and compare it to what all living organisms need to be considered alive. Reproduce, get and use energy, grow,develop, and die, have DNA, and react to the environment. While viruses do have DNA and react to the environment, they cannot grow on their own.