The CaSB Pre-Major provides students with broad, foundational knowledge in the sciences–biology, chemistry, physics, and mathematics–plus an introduction to computer science.

All students must complete the Pre-Major coursework prior to admission to the Major.

CaSB Major Sheet

Please reference the CaSB Major Sheet for Pre-Major and Major course requirements, Concentration information, and Department policies.

NOTE: The CaSB Major Sheet is reflective of requirements effective Fall 2020 and forward. For all students admitted to the Pre-Major prior to Fall 2020, please consult your Degree Audit Report and the CaSB Department Counselor to confirm your Pre-Major requirements.

CaSB Pre-Major Requirements

Effective Fall 2020, students will need to meet the following requirements to be admitted to the Major:

  • Completion of all Pre-Major courses
  • Minimum 2.7 GPA in all Pre-Major courses
  • Minimum grade of C or better in all Pre-Major courses*
  • Minimum 2.0 cumulative GPA

Prior to Fall 2020, students were also required to have a minimum 2.7 GPA in Pre-Major math courses in order to be eligible for admission to the Major. This requirement has been removed effective Fall 2020.

*Students are allowed to repeat up to 2 Pre-Major courses in which they receive a C- or below. Please see our Academic Eligibility page for more details.

Computational & Systems Biology (CaSB) Pre-Major Requirements (effective Fall 2020 and forward):

Life Sciences: 7A, 7B, 7C
Chemistry: 14A, 14B, 14BL OR 20A, 20B, 20L
Physics: 5A, 5B, 5C OR 1A, 1B, 1C
Calculus & Statistics Series Option #1: Mathematics 31A, 31B, 33A, 33B, Statistics 10

Calculus & Statistics Series Option #2: Life Sciences 30A, 30B, C&S BIO M32, Mathematics 33A, 33B, Life Sciences 40

Computer Science: Computer Science 31 OR Program in Computing 10A

Students in certain Concentrations must complete additional lower division courses. These courses do not need to be completed prior to admission into the Major.

Students following the Bioinformatics Concentration must complete:

  • Mathematics 32A*
  • Computer Science 32 OR Program in Computing 10B and 10C 

Students following the Biological Data Sciences Concentration must complete:

  • Computer Science 32

Students following the Biomedical Systems or Systems Biology Concentrations must complete:

  • Mathematics 32A*

*For students completing the Calculus & Statistics Series Option #2, C&S BIO M32 can fulfill this requirement.

CaSB Pre-Major Course Planning

When planning Pre-Major coursework, students have different options for completing the mathematics/statistics, chemistry, physics, and computing requirements. Based on students’ choice of mathematics/statistics series and intended Concentration, students are advised to take certain courses. The decision tree below can help students identify course options.


When planning courses, students must be mindful of pre-requisites. The flowcharts below are meant to help students plan out Pre-Major coursework by depicting the requisites for each series. These flowcharts were last updated August 2020. Always check the Registrar’s Course Descriptions for the most up-to-date requisites.

Other Important Information

All Pre-Major courses must be taken for a letter grade, C or better. Students who receive a C- or below in a Pre-Major course must either repeat the course or petition to have the lower grade count for the Pre-Major. Students who receive 3 or more grades of a C- or below in Pre-Major courses will be dismissed from CaSB. Learn more about repeat policies and academic eligibility here.

Students are subject to any requirement changes in the Pre-Major until officially declared for the Pre-Major. Students are subject to any requirement changes in the Major until they are officially admitted to the Major. Students in the Pre-Major should check their Degree Audit Report (DAR) for remaining Pre-Major requirements and the CaSB Major Sheet for the most up-to-date Major requirements. Please note that the DAR may not show the most current Major requirements while in the Pre-Major status.