Biology Major Guide (USA)

What a biology degree covers

A US biology major begins with a broad foundation — introductory biology, general and organic chemistry, and often physics and calculus or statistics — before branching into specialised areas. Core biology coursework typically includes genetics, cell and molecular biology, evolution, ecology, and physiology.

Biology is one of the most subdivided fields, and many departments let students choose a concentration. Because requirements differ widely between universities, the official course catalogue and degree-requirement sheet are the most reliable guides to what a given programme involves.

• Foundation: introductory biology, chemistry, often physics and statistics/calculus
• Core: genetics, cell and molecular biology, evolution, ecology, physiology
• Most programmes require multiple laboratory courses
• Many offer concentrations or tracks within the major

Common sub-tracks within biology

Departments often organise upper-division study into tracks. Molecular and cellular biology focuses on the machinery of cells, gene expression, and biochemistry-adjacent topics. Ecology, evolution, and organismal biology study populations, ecosystems, biodiversity, and field methods. Microbiology examines bacteria, viruses, and other microorganisms, often with strong laboratory work.

Other common options include neuroscience-leaning tracks, genetics and genomics, marine or environmental biology, and biotechnology, which blends biology with applied and engineering techniques. Track names and structures vary; verify exactly what each university offers on its official department page.

Laboratory and field experience

Hands-on work distinguishes biology study. Wet-lab courses teach techniques such as microscopy, cell culture, PCR and molecular methods, and data analysis. Ecology and organismal tracks often add field components — sampling, observation, and environmental measurement.

Undergraduate research is common and is frequently valued by graduate and professional programmes. Many students join a faculty lab, complete an honours thesis, or take part in summer research. Bioinformatics and computational biology have also grown, so familiarity with data tools and basic programming is increasingly useful. Check each department for research opportunities and lab facilities.

Directions beyond pre-med

Biology is popular among pre-med students, but the degree opens far more than medicine. Graduates pursue research and graduate school (M.S. or Ph.D.), biotechnology and pharmaceutical work, environmental and conservation roles, laboratory and quality positions, science communication and policy, education, and a range of other health professions such as dentistry, pharmacy, physician assistant, nursing, and veterinary paths.

If you are specifically planning for medical school, the pre-med track is a distinct planning layer that sits on top of (and is not the same as) a biology major — see the dedicated pre-med guide. No major guarantees admission to any professional programme; admissions depend on each programme's published criteria, which you should verify on its official page.

Graduate and professional study

Research-focused careers in biology generally require a graduate degree. Ph.D. admission typically rests on coursework in the core areas, research experience, a statement of purpose, and references; funded doctoral programmes are common in the sciences. The GRE is required by some programmes and waived by others, and policies differ — confirm on each programme's official admissions page.

For health professions, separate admission tests and prerequisites apply (for example the MCAT for medical school); consult the official testing organisation and each programme's requirements. For current labour-market context, the U.S. Bureau of Labor Statistics publishes outlooks for biological and life-science roles, updated each edition on the official site.