Which of the following viruses possesses DNA a capsid with icosahedral symmetry and no lipid envelope

Ans. is 'b' Adenovirus Read the following facts and this question will seem very easy : . All nonenveloped viruses (whether DNA or RNA) have icosahedral symmetry. . Nonenveloped DNA viruses PAP - PApova, Adeno, PArvo . Nonenveloped RNA viruses -4 PCR - Picorna, Calci, Reo. Also know . All DNA viruses (whether enveloped or nonenveloped) have icosahedral symmetry except poxvirus which has complex symmetry. . No DNA virus has helical symmetry. . RNA viruses have either icosahedral or helical symmetry : Icosahedral symmetry --> Nonenveloped RAN viruses (PCR --> Picorna, Calci, Reo) and Retro, Flavi, Toga, (Remember - RFT). Helical symmetry --> Rest of the RNA viruses.