Answer:
SARS- CoV- 2 is a virus that infects human by the oral-respiratory way in which the virus enters the body and these viruses have spikes on their surface made of spike proteins that allow these viruses to bind with the infected cell.
The infected cells have ACE2 receptor that is protein present on the surface of the human cells. Binding allows the structural change in the virus to fuse and enter in the cell where viruses reproduce them selves with the cell with cell system.