UPDATE 8/21/15: As we've reported, the Gilbert, AZ school board has apparently decided to add stickers to the books. An example, below, was provided to use by a local viewer:
After a crusading religious group showed up at the Gilbert, Arizona school board meeting with three Republican state senators to complain about the presence of a mention of abortion in an honors biology text book, the board voted to get rid of that material. It was determined that the most efficient way to remove the offending material is to literally remove it - as in, tear the whole page out of the book.
As a service to Arizona honors biology students who want to know what used to be in the gap in their textbook's page numbers, we have preserved page 545 of the seventh edition of Campbell Biology: Concepts and Connections.
[Gilbert uses both the fifth edition (pdf) and the seventh edition (pdf).]
Campbell's AP Biology, 7th edition, pages 981-984:
Campbell's AP Biology, 9th Edition, pages 1015-1018: