NEET BIOLOGY

Detailed explanation-1: -Virion is different from a virus. It is nothing but a virus in an extracellular phase. Furthermore, it is a fully furnished viral molecule consisting of DNA or RNA material. It is also encapsulated by an external protein shell called a capsid.

Detailed explanation-2: -Viroids are free RNA molecules of low molecular weight without any protein coat while viruses can have either RNA or DNA molecules encapsulated in a protein coat. Viroids are smaller in size than viruses. Viroids infect only plants whereas virus infects all types of organisms.

Detailed explanation-3: -A complete virus particle is called a virion. The main function of the virion is to deliver its DNA or RNA genome into the host cell so that the genome can be expressed (transcribed and translated) by the host cell. The viral genome, often with associated basic proteins, is packaged inside a symmetric protein capsid.

Detailed explanation-4: -Viruses (Virus particles or virions) are usually units consisting of nucleic acids and coat proteins called capsids. Viroids consist only of RNA, i.e. they contain no protein at all. Except for a few cases, viruses are not surrounded by a membrane.