Which of the following viruses possesses DNA, a capsid with icosahedral symmetry and no lipid envelope -a) Herpesvirusb) Adenovirusc) Poxvirusd) Papovavirus

All nonenveloped viruses (whether DNA or RNA) have icosahedral symmetry. Nonenveloped DNA viruses → PAP - PApova, Adeno, PArvo Nonenveloped RNA viruses —› 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.