The cell's internal transport system consists of a series of sacs and tubes collectively called

Though I am unsure of the answer myself, I've recently studied cells in school. I believe that the series of sacs and tubes are collectively called the endoplasmic reticulum, located mostly near the nucleus in the center of the plant or animal cell.

When a virus infects a host cell, it uses the cell's machinery to make copies of its own genetic material in a process called replication. finally, during the process of self-assembly, that protein shell and the copies of the virus's genetic material are assembled into new viruses.