Why should a person breathe into a paper bag when she or he is hyperventilating abnormal?

When the body receives more oxygen than it needs, the result can be what's known as respiratory alkalosis (high pH). One of the most common causes is hyperventilating. The point of breathing into a bag is to “re-breathe” your exhaled carbon dioxide (CO2) in the hopes of bringing your body back to a normal pH level.

In other words it slows down there breathing making them calm and also helps for if they want to throw up

Photo means light and synthesis means combination so combination of light

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.