The Undergraduate Major in Biology

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The major begins with a variety of introductory courses related to the different fields of Biology. Students will begin taking these courses, exploratory lab courses, and a selection of additional breadth courses in Chemistry, Math, Physics, and Statistics during their first two years. Advanced elective courses will be taken in the remaining two years. Although not required for any field of study, most Biology undergraduates choose to engage in at least one quarter of research in a lab on campus. Many go on to complete independent research that culminates in an Honors thesis and presentation. More information about the requirements for the B.S. Biology are included here.

BIO Foundations Courses (80-level)
Five courses are required and generally taken by sophomores and juniors

In the next step of the curriculum, students engage with fundamental areas of Biology through a set of six Bio Foundations courses, which cover key foundational disciplines of Biology. Students will take five of the six Bio Foundations courses depending on their area of emphasis within the major. These courses will delve into these fundamental areas of Biology and further build students’ skills in critical scientific thinking, reading the literature, and scientific communication.

Each Bio Foundations courses is offered for 4 units:

  • BIO/BIOHOPK 81 – Ecology (Main Campus: Autumn; Hopkins: Spring)
  • BIO 82 – Genetics
  • BIO 83 – Biochemistry and Molecular Biology
  • BIO 84 – Physiology
  • BIO 85 – Evolutionary Biology
  • BIO 86 – Cell Biology

The general Biology major allows students to choose any five out of the six Bio Foundation courses. Specialized fields of study will require specific Bio Foundations courses, with the remaining courses to be selected by the student, to a total of five. For those courses offered on both the main campus and at Hopkins Marine Station, students may fulfill their requirements at either campus. 

The 80-level Bio Foundations courses must be taken for a letter grade. Questions about the Foundations courses can be submitted to Waheeda Khalfan (wkhalfan [at] (subject: Bio%20Foundations%20Question) (wkhalfan@)).

Inquiry-Based Lab Courses (40-level)
Two courses are required and recommended to be taken sophomore year

These courses provide hands-on exposure to scientific methodology and experimental design. They are inquiry-based and allow students to hone their scientific thinking and lab skills by conducting real biology research. All students, even those who pursue honors, are required to take two lab courses, designed to give a grounding in both lab research and in field research: 


  1. BIO 45, Introduction to Laboratory Research in Cell and Molecular Biology
  2. One of the following:
    • BIO 46: Introduction to Research in Ecology and Evolutionary Biology
    • BIO 47: Introduction to Research in Ecology and Evolutionary Biology
    • BIOHOPK 47H: Introduction to Research in Ecology and Ecological Physiology
Breadth Courses
A variety of Chemistry, Math, Physics, and Statistics courses are required

Courses in Chemistry, Math, Physics, and Statistics will be required. Although specific requirements will vary by specific field of study, students can expect to take the following courses:

  • 2-4 courses in Chemistry
  • 1-3 courses in Math
  • 1-4 courses in Physics
  • 1 course in Statistics

Of the breadth courses in Chemistry, Math, Physics, and Statistics only one may be taken credit/no credit.

Elective Courses (100-level and above)
23 units of electives are required

Upper level courses are offered in more specialized areas of Biology, many of them are seminar-style courses that provide opportunities to explore in depth the scientific literature and to develop ideas for novel areas of research. Students have the option of pursing a general Biology major, or fulfilling specific requirements to pursue a specialized field of study. Regardless of the field of study chosen, all students are required to take 23 units of upper division electives.

For the General Major, students may choose any 100-level or higher BIO or BIOHOPK course, as well as courses from a list of preapproved courses in other departments.

Students choosing a specialized field of study will take a unique combination of course requirements as outlined in their specific area. The fields of study are:

All students may take one elective course credit/no credit. 

A maximum of 6 units of BIO 196-199/X, BIO 290-292, or BIO 296, and a maximum of 3 units of BIO 114A/B/C can count towards this requirement.

Senior Capstone Experience
Students majoring in Biology will be expected to declare which capstone track they intend to follow no later than the start of spring quarter in their junior year of study.

Important note: All undergraduates matriculating as first-year students in 2021-22 or later and graduating in AY 2024-25 or later must complete a capstone. Transfer students who enter in AY 2022-23 or AY 2023-24 and plan to graduate in AY 2024-2025 or later will also be required to complete a capstone.  

The capstone requirement in Biology may be fulfilled via one of four tracks.

Track 1 - Research-based studies leading to a Senior Thesis:

Students who conduct laboratory-based research may fulfill the capstone requirement by submitting a written thesis at the end of their senior year.  The laboratory work may take the form of either basic or clinical research.  All students submitting a senior thesis must complete BIO 199W (Senior Thesis: How to Effectively Write About Scientific Research - offered in winter quarter). Students whose thesis work involves independent hypothesis-driven research that explores biological mechanisms or theory may be eligible for departmental honors. To pursue honors, students must submit an honors petition in the fall of senior year, complete at least 10 units of BIO 199/X (Undergraduate Research), have a GPA of 3.0 or higher at the time of graduation, and present their honors thesis at the departmental Achauer Honors Research Symposium and through the Biology Virtual Showcase website.

Track 2 - Individually designed creative projects - The Senior Reflection:

Students interested in expressing their personal interests in biology via creative or artistic forms (such as writing, music, fine arts, performing arts, photography, film or new media) may enroll in The Senior Reflection (Bio196A, B and C; all three courses are required for this track).  A written proposal on the creative process and scientific significance of the selected topic is generated in the fall (Bio 196A). During the winter quarter in BIO 196B, weekly workshops support the development, production, and refinement of each project. In spring (BIO 196C), projects are finalized and curated for an exhibition, which is held at the end of the quarter. Students are also required to write a final reflection essay.

Track 3 - Individually designed projects - The Senior Synthesis:

Students who wish to conduct an independent, individually-designed capstone project may enroll in the Senior Synthesis.  Such individually-designed projects might involve research internships, business internships, travel-based study, teaching or other forms of community service.  Examples of possible products of these individually-designed capstones include the production of a teaching or business plan, a film or podcast, or a public education campaign.  Students in this track will take two courses (BIO 199Y and BIO 199Z ).  BIO 199Y should be taken in spring quarter of the junior year. This course will be devoted to identifying an appropriate mentor and developing a project proposal, which will be reviewed and approved by course faculty.  Students may engage in project-related internships or activities during the subsequent summer and fall quarters, and must then enroll in BIO 199Z during winter quarter of their senior year.  This course will be focused on the production of the capstone project and preparation for its presentation to the department.

Track 4 - Approved capstone experiences in other departments or interdisciplinary honors programs:

Students may also fulfill their capstone requirement via other approved capstone programs or honors programs, provided that the student’s specific program or project contains a substantial amount of biological relevance or content.  Examples of such programs include the Notation in Science Communication (offered by PWR), Honors in the Arts, and the Ethics in Society honors program.  Students who wish to use this track must submit a petition to the Biology Undergraduate Studies Committee prior to spring quarter of their junior year.

Writing in the Major (WIM)
1 designated writing intensive course is required

Students are required to take one of the Biology university-approved WIM courses. Several of these options can also count toward the electives requirement. WIM must be taken for a letter grade when available. 

Adding Honors
Students who wish to engage in a substantial piece of independent research may add Honors to their major, either the general major or any field of study

Honors is an optional addition to the Biology major. Should students wish to complete the Honors Program, the requirements include:

  • Approved honors proposal
  • 10 units of research in the same lab, enrolled as BIO 199, BIOHOPK 199H, or BIO 199X (Note - If this poses a challenge, we will consider exceptions on a case-by-case basis for students who have completed comparable experience through federal work study, paid research experience, etc.)
  • GPA of at least 3.0 for all courses taken toward the major (excluding research units)
  • Approved honors thesis
  • Presentation of research at the annual honors symposium, either as a poster or an oral presentation

Students apply for honors two quarters prior to their anticipated graduation date (Spring graduates apply in Autumn).