Learn about these early precursors to plants, their use of chlorophyll to make food, and how they differ from algae. View photos of fossils.

Use this question-and-answer format to learn the characteristics of blue-green algae. View illustrations, photos, and representative specimens.

Offers photos and video clips, and extensive research bibliography, and bacterial growth protocols. Find a mailing list and links.

Conservation biologist explains the fundamentals of bacteria and protists. Includes pictures and links to databases and image galleries.

Learn about the organism that causes syphilis and Lyme disease in humans and leptospirosis in animals. Find photos and links to researchers.

Complete overview of bacteria characteristics, physiology, and motility. Offers plenty of photos and illustrations.

Offers the strain lists, genetic sequence maps, and clinical stages of leptospirosis. Find conferences and additional links.

Meet the microbe of the month, browse news about beneficial and dangerous bacteria, and read about typical microbial dwellings. See links.

Learn about the preferred habitat, reproduction, and taxonomy of these one celled Monerans from the Cyanophyta phylum.

Identifies the different species of bacteria in this genus, and discusses the diseases they cause.

View this schematic illustration of the structures that compose bacterial cell walls. See examples of gram-positive and gram-negative membranes.