The Biology of Viruses introduces these strange parasitic entities--little more than packages of genetic information that subvert cells into producing more viruses. This program presents: the discovery of viruses, their structures, how they are studied, and their various modes of infection and replication from the T-4 bacteriaphage to complex retroviruses such as HIV.The Biology of Bacteria shows: the surprising range of behavior seen in living bacteria, how bacteria obtain nutrients through "external digestion," and how to use sterile techniques for culturing and studying them. The program shows the vital roles bacteria play in maintaining the biosphere through oxygen production (by cyanobacteria), decomposition and nitrogen fixation. What is a Protist?, by exploring a diversity of protist groups. Using dramatic new dark field and DIC images of micro-organisms, students can investigate the structure, behavior, feeding methods, reproduction and ecological relationships among the different groups to better understand single-celled eukaryotes. All of the standard protists studied in the laboratory are featured, including Paramecium, Amoeba, Volvox, Spirogyra, and Euglena. A great complement to laboratory study, and a vital tool for understanding the ongoing revision of the ‘Kingdom Protista’.