For BI306, there is one recommended (not required) textbook. It is:
Genetics A Conceptual Approach by Pierce, Benjamin A.
Edition: 5th ISBN: 9781464109461
Format: Hardcover Publisher: W. H. Freeman
Pub. Date: 12/27/2013
You can buy a used copy or rent a copy of this book - I don't care if it is a hardcover, paperback, or eTextbook (hardcover ISBN listed). If you want a cheaper option, the 4th edition of this book is pretty good too (I like the examples and epigenetics section in the 5th edition better). Do not buy the most expensive, most recent 6th edition.