ecological models are often represented using boxes and arrows. in viewing the generic model of nutrient cycling, what do the boxes and arrows mean?

When you are making a guess you are forming a hypothesis

I’m not really sure

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.