replicate via DNA intermediates. These viruses possess an RNA-dependent DNA polymerase called reverse rer transcriptase cel that transcribes the viral RNA to form DNA intermediate. cul a other viruses contain RNA genomes and require their own RNA tim polymerase. These virion enzymes are necessary because cells prir cannot make DNA or RNA from an RNA template (e? Sec org tions 6.8 and 6.12). Such Some viruses contain enzymes that aid in their release from they the host. For example, certain animal viruses contain surface pro rato teins called neuraminidases enzymes that ve glycosidic bonds in glycoproteins and glycolipids of animal cell connective Min thus liberating the virions. Although most virions lack tissue, heir own enzymes, those that contain them do so for good rea- would not be able to produce virions in Wi the son: The host cell enzymes. absence of these extra