Click the link above and follow Steps 1-3 to install and set up Zotero on your computer. Step 4 is optional.
The citation styles used by biology comps students are Cell and The American Naturalist, which you will need to download from the Zotero Style Repository. You will only use one of these citation styles for your comps paper, but if you don't yet know which one you'll be using, it doesn't hurt to download both. Once Zotero is installed and set up on your computer, search for these styles by name in the repository. Once you find the style you want to use, click on it. You will be asked if you want to add the style to Zotero. Click "OK" and the style will be added to your Zotero program.
NOTE: When searching the Zotero style repository, you may see citation styles with similar names, like "Cell Systems" or "Cell Cycle." Ignore these; the citation styles you want are named "Cell" and "The American Naturalist."