Bachelor of Science


Best Online Bachelor's Program in the Nation

- U.S. News & World Report, 2021

Quick Facts

Credits Required: 120
Cost Per Credit: $525
University of Arizona Biology Building

College of Science

Program Details

Explore your interest in biodiversity and the natural world and gain the flexibility to pursue a career in medicine, health, agriculture or environment. The Bachelor of Science in Biology is offered by a top-ranked program renowned for groundbreaking scientific discoveries and a long tradition of involving students in leading-edge research.

The curriculum provides a broad overview of the structure, function and evolution of biological systems from component parts, to organisms, communities and ecosystems. As a biology major, you will choose one of two degree emphases: Biomedical Sciences or Organismal Biology.

As a graduate, you may choose to pursue a career in a wide range of fields including medical and clinical research, healthcare, forensic science, conservation or wildlife biology. Biologists often seek to address grand challenges in medicine, agriculture and environment. This includes viral evolution and global pandemics, quantitative genetics and advanced plant and animal breeding, and biodiversity conservation and global change.

Our graduates are highly successful in gaining admission to graduate and professional programs that lead to careers in medicine, pharmacy, optometry, dentistry, veterinary medicine, law, public health and education.

The online BS in Biology can be completed fully online. However, some post-graduate professional programs do not accept prerequisite courses taken online. Be sure to check the policies for post-graduate programs you may want to attend.

Eligibility: Students must meet general university admission requirements: First Year, Transfer, International and Readmission.

*Residents of some U.S. Territories may not be eligible. Please see our Eligibility & State Authorization page for more information.


CHEM 243A Organic Chemistry Lab I (1-unit) and CHEM 243B Organic Chemistry Lab II (1-unit) are not offered in a fully-online format through Arizona Online. We recommend students who intend to apply to professional health programs post-graduation take both courses in-person at Arizona during summer pre-session (available starting Summer 2022) or an alternative institution for equivalent transfer credit.

The curriculum for this program includes:

    ECOL 182L: Introductory Biology II Lab
    ECOL 182R: Introductory Biology II
    ECOL 302: Ecology
    ECOL 320: Genetics
    ECOL 335: Evolutionary Biology
    MCB 181L: Introductory Biology Laboratory I
    MCB 181R: Introductory Biology II
    BIOC 384: Foundations in Biochemistry

    Areas of Emphasis

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    Biomedical Sciences

    The Biomedical Sciences emphasis is for students who plan to pursue careers in biomedical research, medicine and other health professions. The program of study provides training in systems biology with a focus on anatomy, physiology and biochemistry. This emphasis includes all of the coursework required for admission to medical school.

    Biomedical Sciences Courses
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    Biomedical Sciences

    Courses in this emphasis may include:

    • ECOL 220: Evolutionary Medicine
    • ECOL 379: Evidence-based Medicine
    • ECOL 409: Evolution of Infectious Disease

    View detailed program information

    Biomedical Sciences Details
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    The Organismal Biology emphasis is for students interested in careers as professional biologists and educators. The program of study provides training in systems biology with a focus on animal behavior, genetics, ecology and evolution.

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    Courses in this emphasis may include:

      • ECOL 335: Evolutionary Biology
      • ECOL 302: Ecology
      • ECOL 360: Marine Ecology & Conservation

      View detailed program information

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