Dear Student
Viruses are different from other microorganisms as they are too much smaller comparison to any other microorganism. They are not cells and do not cell organelles. They cannot multiply on their own. For this, they need to enter a living host cell.
Viruses are ultramicroscopic organism s that are visible only through electron microscope. They are smaller than bacteria. They cannot reproduce by their own as they lack the required machinery for replication. Therefore, they need to infect a host cell. The virus gets inside the host cells and makes hundred and thousands of copies of itself by using the host machinery.
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