The inspiratory reserve volume measures the
amount of air remaining in the lung after a maximal exhalation
amount of air that the lung holds
amount of air that can be further exhaled after a normal breath
amount of air that can be further inhaled after a normal breath

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.

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