I'm currently an undergraduate math student and researching on the internet I discover that exists an area called "biomathematics". Looks so interesting. They use the graph theory and topology to describe the cells and DNA structure. Was love at first sight, because I really love maths and biology.
I'm reading the book "Clinically Oriented Anatomy" of Keith L. Moore and "Essential Cells Biology" of Bruce Alberts, but I don't know if I'm doing right. If anyone know how to start to learn this science I would really appreciate it.
Springer have a series of books called Lecture notes in Biomathematics most of which should be in the maths department library. I don't know if they allow undergraduates in in your university. If they don't then smile nicely at the librarian and sound enthusiastic they sometimes make exceptions.
The best idea is to look through the research interests of the staff in your department and see if anybody's researching math.bio. Then just go and talk to them about it.