Hello everyone. I'm new to scienceforums.net and I have some questions about the anatomy of bacteria. I've arrived at these questions because I'm a 3D computer graphics artist working for a company that makes educational software in the fields of medical anatomy, biology, and other areas of science. There are a lot of tidbits I'm wondering about, but I'm going to start with just a few questions so as not to overwhelm the good folks here.
Chromsomes: Do all bacteria have closed-circle, single-helix chromosomes? I've seen a few sources saying this but haven't found a lot about it, and have seen some diagrams showing a sort of spiral strand-shaped chromosome whose ends do not connect to each other. Also, I read that Brucella Abortus has two circular chromosomes; are there any other bacteria with more than one chromosome?
Plasmids: Are there certain genera and/or species that usually contain naturally-occurring plasmids, or does it vary per specimen? Is there only one instance of any given plasmid in a specimen, or several? Is there a general rule to determine which bacteria with naturally-occurring plasmids have single-stranded plasmids, and which have double-stranded plasmids?
Thanks much for whatever insight you all are able to provide! If there are recommended resources that address these questions (or a different forum I may have missed), I'm all ears.
P.S. For those of you who are curious, the company I work for is Cyber-Anatomy at http://www.cyber-anatomy.com/ and my own art portfolio is at http://www.jariensky.com
