Microbial World

Organisms Infectious agents

I Domain B^S^Ta Rua® I Viruses Viroids Prions

Prokaryotes Eukaryotes (unicellular)

Algae Protozoa Fungi Helminths

(unicellular or (unicellular) (unicellular or (multicellular multicellular) multicellular) parasites)

multicellular) parasites)

Protists

Figure 1.12 The Microbial World Although adult helminths are generally not microscopic, some stages in the life cycles of many disease-causing helminths are.

The distinguishing features of the nonliving members of the microbial world are given in table 1.4. The relationships of the major groups of the microbial world to one another are presented in figure 1.12.

1.5 Size in the Microbial World 13

Table 1.4 Distinguishing Characteristics of Viruses, Viroids, and Prions

Viruses

Viroids

Prions

Obligate intracellular agents

Consist of either DNA or RNA, surrounded by a protein coat

Obligate intracellular agents Consist only of RNA; no protein coat

Obligate intracellular agents Consist only of protein; no DNA or RNA

Organic Gardeners Composting

Organic Gardeners Composting

Have you always wanted to grow your own vegetables but didn't know what to do? Here are the best tips on how to become a true and envied organic gardner.

Get My Free Ebook


Post a comment