What Does a Biology Major Mean?

By Briana Kusuma | UTS Staff Writer | SQ Online (2013-14)

When you ask a UC San Diego undergraduate what their major is, their answer is likely to be one of the biology categories–which is not too surprising when you consider the fact that 21% of UCSD undergraduates are biology majors. There are nine majors within the biological division: general biology, bioinformatics, ecology, behavior and evolution, human biology, microbiology, molecular biology, physiology and neuroscience, and biochemistry and cell biology. With these many sub-categories, how do you even go about deciding which one is for you?

General Biology is just as the name states: general. Unlike the other biology majors, you are not limited to certain parts of the body that you want to study or even humans at all. Free reign means that students in this major are free to take whatever biology upper divisions they’d like and have more choices in classes.

is a major that is noticeably different from the other categories. More based on mathematics and computer science, the lower and upper divisions here incorporate many more computer engineering classes and also require enrollment in the specialized math classes, such as the MATH 20 series. The requirements are much more specialized and strict, as you cannot usually choose between alternatives for a class.

Ecology, Behavior and Evolution looks at the relationships between organisms and their environments, taking a different approach to applying biology to real life. This major offers some of the most flexible career options; graduates may go into forestry, education, ecological medicine, and so much more. However, this also means that the upper division classes for this major are vastly different from most of the biology majors, as many of the applicable classes are focused on ecology and evolution instead of the organismal body.

is particularly tailored to students interested in health fields. As its name suggests, its focus is on the study of humans, particularly the human body and the way diseases affect it. While some of the required upper division classes briefly dabble in molecular biology, its core focus is on the human body. However, the lab requirement does offer students diverse options to choose from, ranging from aquatic ecology to recombinant DNA.


Physiology and Neuroscience at first glance can seem like a more specific version of the Human Biology major. While it is also tailored to those interested in going into a health field by encompassing the study of the human body, this major emphasizes neurobiology, while Human Biology does not.


Molecular Biology is a field that has the intention of preparing students for research by emphasizing concepts and techniques of experimental molecular biology. The first difference is in the lower divisions; students in this major are not required to take the entire BILD series, but have to take the MATH 20 series. The upper division requirements are also stricter, as there is no list of classes to choose from, except for the lab and elective requirements.

is another major designed for those going into health-related careers but focuses on microbiology and viruses. This major takes a much more in-depth look at biology studying microorganisms; however, similar to many of the other biology majors, there are upper division classes in this major that emphasize the medical applications of microbiology, such as immunology. Much like molecular biology, this major does not require the entire BILD series and the upper division classes are just as rigid in lack of choice.

is a major designed to be flexible in career callings, stretching from medical school to research in a wide variety of other branches of biology, such as biophysics and cancer biology. Students are able to learn biology from a cellular level and organismic processes from the perspective of a different science, along with developing laboratory techniques through extra lab requirements. Like molecular biology and microbiology, students do not have to take the entire BILD series. The upper divisions are pretty similar to the other biology majors and can be considered more flexible, as there are a variety of classes to choose from when fulfilling one of the upper division requirements.

Overall, while most of the biology majors may share similar class requirements and are designed for the same general careers, they differ greatly from each other once examined closely. The focuses of each major are tailored to specific branches of biology, thus possibly impacting what classes students have to take to get their degrees.

For more information about the various biology majors and advising, visit UCSD Division of Biological Science’s undergraduate page.