Students begin the Biology major with Foundations of Biology (BIOL 101), Intermediate Cell Biology and Genetics (BIOL 201) and Evolution in Action (BIOL 202). Foundations of Biology gives an overview of the fundamental themes of biology within the context of a specific biological system, which varies from section to section. Intermediate Cell Biology and Genetics course builds on the material covered in BIOL 101, and includes biological molecules, cell structure, cell signaling, metabolism, and classical and molecular genetics. Evolution in Action is an examination of evolutionary processes in the context the of important biological themes of information transfer, the exchanges of energy and materials, reproduction and the transmission of genetic information, and the dynamics of biological populations and communities. BIOL 101 and 201 are meant to be taken in the first year, while BIOL 202 should be taken during the sophomore year, as it is a prerequisite for many upper-division courses. Entering students may be eligible for credit on the basis of the Advanced Placement test in Biology, the International Baccalaureate or the College Level Examination Program (CLEP).

In addition to the three core courses, Biology majors take 20 credits in upper-division (300-level) courses. These courses allow students to explore a number of specialties and refine their particular interests.

The capstone requirement for the Biology major can be completed though any of the following options:

1. An Honors Thesis (BIOL 398), Biological Research (BIOL 372) or summer research (at CSB/SJU or elsewhere) that satisfies institutional capstone criteria.
2. Completion of hands-on research in the context of the 2-credit Senior Capstone in Biology course (BIOL 380 - LAB option).
3. Completion of a review paper in the context of the Senior Capstone in Biology course (BIOL 380 - LIB option).

Students pursuing any of the capstone options are required to make a formal presentation on campus or at some other venue. Senior Capstone in Biology (BIOL 380) must be taken during the student’s senior year.

The interdisciplinary nature of Biology means that students must take courses outside of the Biology Department for a meaningful understanding of the subject. Introduction to Chemical Structure and Properties (CHEM 125), Purification and Separation Lab 1 (CHEM 201) and Probability and Statistics (MATH 124) are required of all Biology majors. One additional course from a list of approved courses that include offerings in Physics, Chemistry, Math, Computer Science and Environmental Studies is also required.