A virus is essentially DNA or RNA surrounded by a coat of protein. It is not made of a cell, and cannot maintain a stable internal environment
Though viruses are not considered living, they share two important traits with living organisms. They have genetic material like all cells do (though they are not made of cells), and they can evolve.
Viruses infect a variety of organisms, including plants, animals, and bacteria, injecting its genetic material into a cell of the host organism. Once inside the host cell, they use the cell’s own ATP (energy), ribosome’s, enzymes, and other cellular parts to make copies of themselves.
o viruses cannot replicate or reproduce on their own; they rely on a host cell to make additional viruses.
Viruses and Human Disease
Viruses cause many human diseases. In addition to the flu and the common cold, viruses cause rabies, diarrheal diseases, AIDS, cold sores, and many other diseases.
A virus is composed of DNA or RNA surrounded by a coat of protein.
“Infections are not viewed as living things since they can’t repeat without anyone else, and they are not included cells.”