Patent protection for design patents only lasts for 14 years after the patent is granted, so they offer six years less protection than other patent types. Unlike plant and utility patents, however, no maintenance fee is required to keep a design patent active.
A virus is a small, infectious agent that is made up of a core of genetic material surrounded by a shell of protein. The genetic material (which is responsible for carrying forward hereditary traits from parent cells to offspring) may be either deoxyribonucleic acid (DNA) or ribonucleic acid (RNA).
The capsomers of helical viruses are composed of a single polypeptide and are also called protomers. All viruses of animals, except for poxviruses which have a complex structure, are minimally composed of a nucleocapsid which is the capsid surrounding the nucleic acid. capsid is composed of structural units called capsomeres. Its symmetry may be cubic or helical. A protein coat that covers the nucleoprotein core or nucleic acid (RNA, DNA) of a free virus particle or phage, which may have icosahedral symmetry and itself be enclosed in an envelopeâe.g., Togaviridae.