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Viral Types Based on Genetic Material and Replication Mechanism


Viruses contain either RNA or DNA as their genetic material. Some viruses have double strands (ds) while others have single strands (ss) of RNA or DNA. Single strands in a viral genome can be coding (plus) or noncoding (minus). The means by which each type of virus replicates in the host cell depends on it type of genetic material.

The diagram below shows the replication mechanism of which of the following virus types?

Celeste R. Wirsig-Wiechmann Created for Copyright 2016. All rights reserved.


Class I dsDNA adenovirus (containing plus and minus DNA strands).


Class II ssDNA parvovirus (containing plus or minus DNA strands).


Class III dsRNA virus (containing plus and minus RNA strands).


Class VI ssRNA virus (containing ONLY minus RNA strands).


Class VII ssRNA retrovirus (containing ONLY plus RNA strands).