Here are some resources and links.
Purdue Owl - Work cited
This link will help you cite any references you use.

Prentice Hall Biology
This is the link to your biology book.

National Geographic
Good resources for all areas of science.

The Biology Project
Arizona State University - Good resource for all biology subjects. This is also where the Online Onion Root Tip Mitosis lab is located.

The Biology Corner
A really good resource for all subjects in biology for students.

Top 10 Biology Resources for Students provides 10 top resources to help students with biology homework.

Biology Online
A great site for definitions. Also a discussion board and contains a wiki dictionary for biology terms.

The Biology Place
Prentice Hall (your book) website that is a quick reference for biology terms and definitions.

Cells Alive
Having trouble understanding cell processes such as mitosis, meiosis, diffusion, etc., cell's alive provide animated videos of these processes.

Chemistry Homework Help
Good place to help understanding basic chemistry for the biology student and to get help with your homework.

Science Daily
Provides daily news of what is occurring in science. Good current event resource.

Biology 101
Gives you study guides, flash cards, etc., for many subjects.