This book is part of a book series called Issues in Focus Today .

There are 104 pages in this book. This book was published 2009 by Enslow Publishers .

Kristi Lew is a former high school science teacher with degrees in biochemistry and genetics. After years in the classroom and cytogenetics laboratories, she is now the owner of a professional K-12 educational writing service that specializes in writing nonfiction science books for students and teachers.