Physiology vs. Biology: What’s the Difference?

For anyone with a curious mind, pursuing a future in science may seem like an obvious choice. In such a vast field, however, choosing the right major can feel overwhelming.

Throughout your time in school, you’ve hopefully had a chance to explore many different areas of scientific study. If topics like life and nature inspire you, you may find yourself leaning toward the study of biology or physiology. But how do they differ, and which one should you choose?

In this article, we’ll look at what you can expect from physiology vs. biology—both during college and beyond.

What Will I Study in Physiology?

Physiology is a sub-discipline of biology that pertains to the inner workings of a living organism. From each organism’s molecular mechanism to their organs and systems, physiology asks questions about the physical and chemical functions of living things.

Physiological science is often studied alongside anatomy, and while the two are related, there’s a subtle difference. Anatomy is the study of structures and physiological processes within the organism; physiology deals with how these systems work and interact.

Studying physiological science involves plenty of vocabulary (especially of Greek and Latin origin) and a grasp of physics and chemistry. Because you’ll be literally digging into the cells, tissues and muscles of living beings, a strong stomach is also recommended.

Here are some examples of physiology courses you’ll find at the college level:

• BIOL 201 - Anatomy and Physiology I
• BIOL 202 - Anatomy and Physiology II
• BIOL 315 - Animal Physiology
• BIOL 370 - Mechanisms of Development

Potential Career Paths in Physiology

Because physiology often focuses on the ideal function of the body, studies in physiology tend to lead students to the medical field. Whether that be in a lab or a clinical setting depends on your specific career goals.

Lab work includes jobs as a lab technician in a hospital, a research assistant or a coordinator for clinical trials. If this is the kind of work that excites you, you may want to pursue a bachelor’s of science with a concentration on physiology and anatomy.

Another potential career path is exercise physiology—a field the Bureau of Labor Statistics (BLS) states is growing at a rate of 13% with a median annual salary of $50,280. Working directly with patients to determine why their body is running less-than-optimally (by studying their cardiovascular system or immune system, for example) can be an extremely rewarding career.

A background in physiology would also be an asset for work as a science writer or medical sales representative. 

What Will I Study in Biology?

Biology is the study of life as a whole. While biology includes physiology under its umbrella, there’s so much more to this natural science. Biologists are interested in the roles, origin and distribution of organisms—both independently and within their ecosystems.

Branches of biology include:

• Biochemistry (exploring chemical processes within living organisms)
• Botany (the study of plants)
• Microbiology (the study of microorganisms)

In general, biological science focuses on life and all things living, which means you will spend plenty of time on evolution, cells, energy and genetics. The discipline also includes a healthy dose of mathematics, physics and chemistry, although there is a difference in focus depending on if you choose to pursue a biology BA vs. BS degree. 

In college, a biology course load is as varied as the field, with courses like:

• BIOL 210 - Cells and Systems
• BIOL 220 - Ecology and Evolution
• BIOL 230 - Genes and Genomics
• BIOL 240 - Biostatistics
• BIOL 340 - Infectious Disease
• BIOL 350 - Conservation Ecology
• CHEM 251 - Organic Chemistry I
• PHYS 161 - Physics I: Mechanics and Heat