"animals are not subject to procedures that involve pain or distress or would be required to use pain-relieving drugs. routin procedures such as injections and blood sampling from veins that produce only mild, transient pain or discomfort are reported in this category."

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.

The name of the instrument that the scientist uses is called a microscope.a microscope is used to view objects which is not visible to the naked eyes