A beautiful masterpiece of the (virus is a small infectious particle that can replicate only inside the living cells of an organism. Viruses are much smaller than bacteria, and they are usually composed of a nucleic acid molecule (either DNA or RNA) surrounded by a protein coat. Some viruses also have a lipid (fatty) envelope surrounding the protein coat. The shape of a virus can vary greatly and can be quite complex. Some viruses are shaped like cylinders or rods, while others are shaped like spheres or cubes. Some viruses are even shaped like more complex structures, such as helical structures or icosahedra. The size of a virus also varies greatly, with some viruses being as small as 20 nanometers in diameter and others being as large as 300 nanometers in diameter:1.3), by (Margaret Macdonald Mackintosh and Albrecht Dürer:0.8), (Tempera and graffiti:0.8), (painting:0.3) | Painting