A virus is basically a tiny bundle of genetic materialâeither DNA or RNAâcarried in a shell called the viral coat, or capsid, which is made up of bits of protein called capsomeres. Some viruses have an additional layer around this coat called an envelope. That's basically all there is to viruses. virus is basically a tiny bundle of genetic materialâeither DNA or RNAâcarried in a shell called the viral coat, or capsid, which is made up of bits of protein called capsomeres. Some viruses have an additional layer around this coat called an envelope. That's basically all there is to viruses.
For all United EconomyÂ® tickets, Premier Gold members are eligible for two complimentary checked bags at 70 pounds (32 kg) each for travel between the U.S., Canada, Puerto Rico and the U.S. Virgin Islands.
Carry on bag: $25 for economy fares if paid at time of initial fare purchase; $50 at departure gate; Free for Classic Plus fares and for summit and ascent frequent flyer members. First checked bag: $20 â $25 for Economy, free for Classic Plus fares.