This activity assumes that students have received information about viral structure, the viral replication cycle, differences between RNA and DNA viruses, and some effects of viruses on living tissues. It also assumes general student knowledge about evolution, including concepts such as variability and natural selection. Teacher Instructions References on viral diseases should be available to students for the research part of this assignment. In addition to biology textbooks, anatomy and physiology textbooks, and virology texts would be helpful. This activity could be used as a summary activity in a unit on viruses or as an activity within an evolution unit.
Viruses are submicroscopic, obligate, intracellular parasites.
The debate rages concerning this question. Thus, Aristotelian philosophy suggests that viruses do live. Viruses require living cells for replication or reproduction. Many viruses require a specific cell type to act as a host. Once the virus locates its cell host, it attaches or adsorbs to that cell.