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Introduction to Viruses

Author(s): Christine Herrmann, PhD

How Do Viruses Differ From Other Organisms?

Viruses are distinct from living organisms. They are not alive. Because of their small size, they do not encode enough genetic information to perform all the functions of life. They can reproduce only within a living host cell, where they usurp the cellular components they need to reproduce. 

Because viruses are not cells, they do not undergo normal cellular processes, such as cell growth and division. They are incapable of transforming energy on their own or of producing and assembling the complex machinery needed for protein synthesis. Viruses carry only the minimal information (four to several hundred genes) needed to take over a host cell and create more viruses.

Funded by the following grant(s)

Video and transcript courtesy of Wah Chiu, PhD, National Center for Macromolecular Imaging at Baylor College of Medicine. Funding for the video provided by NCMI, NIH.