Biology and Physiology Resources

Yahoo's Diseases Category (http://dir.yahoo.com/Health/diseases_and_conditions/) for links to just about any disease you can think of, and quite a few that you had NEVER thought of!
CDC's Traveler's Health (http://www.cdc.gov/travel/index.htm) gives information about disease outbreaks in different parts of the world, as a warning to travelers.
eNature (http://www.enature.com/) has field guides for critters and plants.
Enchanted Learning (http://www.EnchantedLearning.com/Home.html) has diagrams and brief descriptions of many animals. Use the search tool at the top of the page for the fastest way to locate a specific animal.
Biodiversity and Biological Collections (http://www.biodiversity.uno.edu/) goes from microbes to mammals, this site has links to critters, plants, and organizations and associations where you can get even MORE information.