Microbiology 9th Edition by Laura Black, Jacquelyn Black

تمرين 29

Viruses were first described as "filterable agents" meaning that
(a) They were often discovered on filters used to retain mi crobes
(b) The filters that were used to sterilize microbial media would trap viruses
(c) They would pass through filters that were capable of re taining the smallest known bacteria
(d) They were found to aggregate into structures that served as coarse filters.