BA in Biology

The Biology major provides students with a breadth of understanding across the full range of biological disciplines as well as an opportunity to explore one of several specialized areas in greater depth. Required coursework for the major and different specializations establishes a core of fundamental knowledge in biology and related sciences. Students build on this foundation through a variety of lecture, laboratory, field, and seminar courses that offer them the opportunity to focus on specific disciplines. The development of laboratory and field skills is encouraged through elective participation in the extensive, cutting-edge research activities of the department’s faculty. Students graduate with the skills and intellectual base for employment in the burgeoning life sciences job market or for further education, including both graduate programs and professional schools.


The Biology major requires a total of nine courses in biology and a total of six to seven related courses in chemistry, math/computer science, and physics.

Beyond Introductory Biology, at least three major courses must be at the 300+ level and three major courses must be lab courses taken in the BU Biology Department (the 300+ and lab requirements can overlap).

A grade of C or higher is required for major credit in all courses except corequisite chemistry courses. A grade of C– or higher is required for major credit in corequisite chemistry courses.

Course titles and full descriptions are located in the Courses portion of this Bulletin. Unless otherwise noted, all required courses are 4 credit hours.

Introductory Biology (2 courses)

  • CAS BI 107 (or CGS NS 201)
  • CAS BI 108 (or BI 116)

Breadth Requirement (3 courses)

Choose one course in each of the following three areas:

Cell & Molecular Biology (CM)

  • CAS BI 203 (or BI 213 or BI 218*) or
  • CAS BI 206 (or BI 216)

Physiology and Neurobiology (PN)

  • CAS BI 315* or
  • CAS BI 325 (or NE 203*)

Ecology, Behavior, Evolution (EBE)

  • CAS BI 225 or
  • CAS BI 260 or
  • CAS BI 303* or
  • CAS BI 306* or
  • CAS BI 309 or
  • CAS BI 407*

*Course will also count toward the three-lab requirement.

Additional Electives (4 courses)

^ These electives can be any 4-credit courses offered by the Biology Department and/or eligible courses under the Optional Programs section of this Bulletin page.

Please note the following exceptions (which cannot be used toward the major):

  • CAS/MET BI 105
  • CAS/MET BI 106
  • CAS BI 114
  • CAS BI 119
  • CAS BI 196
  • CAS/MET BI 211

Note: After introductory biology, a minimum of five courses must be taken in the BU Biology department (i.e., have a CAS or MET BI or BI cross-listed course designation). A maximum of four MET courses may be counted as credit toward the BA degree. In addition, at least three courses must be at the 300+ level and three must have a laboratory component. Some of these requirements can overlap (e.g., BI 315 simultaneously counts as a breadth requirement, a 300+ level course, and as a lab toward the three-lab requirement). Nonetheless, it is counted only as a single course toward fulfillment of the major.

Related Requirements (6–7 courses)


Choose one of the following tracks (in consultation with your major advisor):

Standard Track (recommended):
  • Choose one of the following general chemistry sequences:
Sequence I Sequence II Sequence III
CAS CH 101 &
CAS CH 102 (or CH 116)
CAS CH 109 &
CAS CH 110
CAS CH 111 &
CAS CH 112


  • Choose one of the following organic chemistry courses: CAS CH 203 (or CH 211 or CH 218)
Alternative Track (not acceptable for most pre-health careers):
  • CAS CH 171^

^ Or any completed general chemistry sequence from the standard track


  • CAS CH 172 or CH 174

Note: It is recommended that the standard track general chemistry sequence (or alternative track’s CH 171 & 172 or CH 171 & 174) be taken concurrently with BI 107 and BI 108 during freshman year. Most Biology majors complete the standard track and continue onto a fourth semester of chemistry (CH 204 or 214), which is a requirement for medical and other professional schools. Students contemplating application to medical school are also advised to take biochemistry (CAS BI 421/422 or CH 373) in their junior or senior year.

Mathematics/Computer Science

Choose two courses from the lists below. At least one course must be calculus or statistics:

Calculus Courses:
  • CAS MA 121
  • CAS MA 122
  • CAS MA 123
  • CAS MA 124
  • CAS MA 127
  • CAS MA 129
  • CAS MA 196

Note: Students cannot take more than one of the following for credit: CAS MA 121 or 123; similarly, students cannot take more than one of the following for credit: CAS MA 122, 124, 127, or 129.

Statistics Courses:
  • CAS MA 115
  • CAS MA 116
  • CAS MA 213
  • CAS MA 214

Note: MA 113 will not satisfy major requirements. Students cannot take more than one of the following for credit: CAS MA 113, 115, or 213; similarly, students cannot take more than one of the following for credit: CAS MA 116 or 214.

Computer Science Courses:
  • CAS CS 105
  • CAS CS 108
  • CAS CS 111


Choose one of the following sequences:

  • CAS PY 105 & 106 or
  • CAS PY 211 & 106 or
  • CAS PY 211 & 212 or
  • CAS PY 241 & 242

Optional Programs

Optional Related Courses

A maximum of two approved courses outside the Biology Department may count as Biology electives. These approved courses include:

  • CAS BB 522^
  • CAS CH 373
  • CAS PS 338
  • GMS BT 404
  • GMS BT 426 (NOT accepted toward the three-lab requirement)
  • GMS BT 432
  • GMS BT 456
  • GMS BT 465
  • SAR HS 251
  • SAR HS 360 (NOT accepted toward the three-lab requirement)
  • SAR HS 369 (NOT accepted toward the three-lab requirement)
  • SAR HS 370 (NOT accepted toward the three-lab requirement)

^ Course will also count toward the three-lab requirement and is not considered an outside course.

Marine Semester (MS)

The Marine Semester is offered every Fall Semester. Students are required to apply to the program. They then select one course during each of four “blocks.” Each block comprises 18–20 class days. All Marine Semester BI-coded courses count as major electives and toward the requirement for three-lab courses.

Please see the Boston University Marine Program (BUMP) Bulletin page for an updated list of MS courses. Students may also refer to the BUMP website for additional information about the Marine Semester.

Tropical Ecology Program (TEP)

The Ecuador Tropical Ecology Program is offered every Fall and Spring Semester. Students are required to apply to the program. They then take four ecology courses based on field research. All the TEP courses count as major electives and satisfy the requirement for three lab courses.


Please visit the Study Abroad web page for prerequisites and additional information.

Undergraduate Research in Biology

While research is not required by the major, undergrads are encouraged to participate in research during their time at Boston University. Undergraduate research courses are available at all levels and require students to submit an application and receive approval by the Director of Undergraduate Studies.

Freshman BI 191/192 2 credits
Sophomore BI 291/292 2 credits
Junior BI 391/392 2 or 4 credits
Senior BI 491/492 4 credits
Senior (Honors) BI 401/402 4 credits

Notes: Up to two 4-credit semesters can be used to fulfill major electives (these semesters do not need to be taken consecutively). One of these two semesters can be used toward the three-lab requirement. Both 2- and 4-credit research count toward graduation credits.

Honors Research in Biology (CAS BI 401 & 402) requires an overall GPA of 3.5. Students must complete two semesters of 4-credit research and one semester of the Honors Seminar (CAS BI 497/498). Honors students must complete and defend a written senior thesis.

Please visit the Biology Department website for additional information regarding undergraduate research in biology.

Modular Medical Integrated Curriculum (MMEDIC) Program

Juniors and seniors who have been admitted to the Modular Medical Integrated Curriculum (MMEDIC) program, with the appropriate prerequisites and approval from the director of the MMEDIC program, may register for certain courses that have been developed for this program. The MMEDIC program offers an integrated curriculum composed of undergraduate and medical school-related courses that facilitate the transition to the curriculum at the School of Medicine. Those interested in early admission to the Boston University School of Medicine through the MMEDIC program should apply through the Pre-Professional Advising office (100 Bay State Road, 4th Floor) at the beginning of the second semester of their sophomore year.

The following courses may count toward the biology major for students enrolled in the MMEDIC program:

  • GMS AN 722
  • GMS BI 751
  • GMS MI 713
  • GMS PH 730
  • GMS PH 731

Note: Students enrolled in the MMEDIC program may petition for up to three MMEDIC courses to be accepted toward the biology major. MMEDIC students must take a minimum of four non-MMEDIC courses beyond the introductory level in the Department of Biology in order to fulfill the department’s residency requirement.

Additional Information

Please see the Department of Biology portion of this Bulletin for information on the following topics:

  • Advanced Credit (AP & IB Exams)
  • Department Residency Requirement
  • Intercollege Cross-Registration
  • Premedical Students
  • Study Abroad Programs