The abundance an elements is the measure of their proportion in a given environment. Their abundance can be measured by mass, molar, atomic or volume fraction.
Hydrogen is the most abundant element in organisms or throughout the Milky Way. It composes water and organic matter. Oxygen comes in third place since it is present in the majority of organic components.
Viruses needs to inject the virus to an organism's body, or host cell and duplicate as many viruses, so it can be able to insert it's own clones and take over the body sooner :3
