But Social Security was never meant to be the only source. of income for people when they retire. Social Security. replaces about 40 percent of an average wage earnerâs income. after retiring, and most financial advisors say retirees will. need 70 percent or more of pre-retirement earnings to live. comfortably.
DNA viruses. Originally viruses were grouped and named according to the disease they cause, even if they are not closely related. For example Hepatitis A is an RNA virus and Hepatitis B is a DNA virus, but they both cause liver disease.Nowadays, however, viruses are grouped by their shared characteristics in much the same way as plants and animals are. All but one of the DNA virus families use double stranded DNA as their infectious 'code'.riginally viruses were grouped and named according to the disease they cause, even if they are not closely related. For example Hepatitis A is an RNA virus and Hepatitis B is a DNA virus, but they both cause liver disease.
Virus Replication. Genomes of RNA or DNA viruses exist in a considerable variety of sizes and shapes, from small molecules of single-stranded RNA or DNA to large double-stranded molecules that may be linear or circular.equires the presence of a viral fusion protein in the virus envelope, e.g. influenza haemagglutinin; retrovirus envelope glycoprotein. These mechanisms are shown in three different infection cycles for RNA or DNA viruses.