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.

Introductory Courses (60-level)
One course is recommended for Freshmen and Sophomores

Although no longer required, the 60-level Biology courses are the starting point for the major. These interactive courses cultivate excitement about Biology and build the intellectual, quantitative and communication skills required to succeed in the major. 60-level Biology courses have no prerequisites. 

BIO 60: Introduction to Problem Solving in Biology: Why is Lyme disease spreading? How does HIV become drug resistant? How do other animals affect our disease risk? In BIO 60 students will examine actual case studies to experience how different scientific approaches are used to battle infectious disease. They will evaluate information presented in the popular media and the scientific literature, and will directly participate in the scientific process through hands-on collection, documentation and analyses of authentic scientific data. Students will cultivate their scientific curiosity by discovering the natural world with a Foldscope, the ‘origami paper microscope’ ( Students will build critical thinking skills by creating hypotheses, and designing experiments that pertain to problems in infectious disease. Students will work in teams to expand their thinking and will practice communicating science to different audiences.

BIO 61: Science as a Creative Process:  What is the process of science, and why does creativity matter? Students will delve deeply into the applicability of science in addressing a vast range of real-world problems. This course will cover how to ask a well-posed question, how to design a good experiment, how to collect and interpret quantitative data, how to recover from error, and how to communicate findings. Course topics will include experimental design, statistics and statistical significance, formulating appropriate controls, modeling, peer review, and more. The course will incorporate a significant hands-on component featuring device fabrication, testing, and measurement, using the Arduino microcontroller and electronic sensors. The final assignment will be to develop and write a scientific grant proposal to test a student-selected myth or scientific controversy. Although helpful, no prior experience with electronics or computer programming is required.

BIO 62: Microbiology Experiments: Microbiology is a major foundation of all modern biology. Many aspects of experimental strategy, logic, and analysis originated in the fields of bacterial genetics and physiology. In BIO 62, we will use prokaryotic biology to review fundamentals of molecular biology and energetics, and in lab work we will work with experimental design and data interpretation. Research on prokaryotes has greatly expanded through genomic and population analysis, and we will use these approaches to ask questions about the hidden worlds around and inside us: the microbiome.

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 1 96-199, BIO 290-292, or BIO 296, and a maximum of 3 units of BIO 1 14A/B/C can count towards this requirement.

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).

Checklist of Requirements by Field of Study

Students will complete the requirements for the general major or any of the seven fields of study: