MCAT Biology and Biochemistry Topics: What’s Tested on the Exam

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It probably comes as no surprise to test-takers that MCAT biology questions and MCAT biochemistry questions are a crucial part of the exam. The MCAT exam is designed to test a candidate’s fitness for medical school. As such, much of the science material is geared towards living systems, biology, and the human body. The Biological and Biochemical Foundations of Living Systems section of the MCAT is the most biology-heavy section, with 59 questions devoted to cellular biology, molecular biology, physiology, biochemistry, and organic chemistry. So what MCAT biology and biochemistry topics do you need to know? Take a look!

MCAT Biology Topics

65% of the Biological and Biochemical Foundations of Living Systems section focuses on biology. Specifically, it focuses on introductory biology: taking two semesters is good preparation for this section. When it comes to biology, the MCAT tests five general areas the most. These are:

  1. Cell Biology. Biology is the study of living organisms and all living organisms are made of cells. For the MCAT, you need to be familiar with organelles, cellular transport, cell division, and cell signaling.
  2. Microbiology. Humans consist of eukaryotic cells that interact with a variety of microorganisms, including bacteria and viruses. These two can be pathogenic and are the source of many illnesses. You will need to know about the structure of these microorganisms, how they replicate, and how they can cause disease.
  3. Genetics. Genetics is a topic that many students are introduced to at an early age. You may have heard about DNA or even RNA as early as elementary or middle school. As you continued onto high school and then college, you delved deeper into the material, learning more advanced genetics concepts. The good news is that you do not need to know genetics to the same depth as a college genetics class. However, there is still quite a number of genetics concepts on the MCAT, which is why we’ve written a whole entire post on what you need to know about genetics for the MCAT.
  4. Physiology. Human physiology is the study of the organ systems within the body and is more relevant to medicine than any other topic on the exam. It’s a lot of material but developing a good foundational concepts of the basics will help you in medical school. For the MCAT, you will need to know all the organ systems, including the nervous system (including the structure and function of the eye), endocrine system, circulatory system, hematologic system, respiratory system, lymphatic system, immune system, renal system, gastrointestinal system, muscular system, skeletal system, integumentary system, and reproductive system.
  5. Hormones. From studying physiology, you will learn about the important role of hormones in regulating all the organ systems. It takes a lot of effort to memorize all of the hormones but you will have to do it for the MCAT. As another major topic on the MCAT, we also have a dedicated post on what to know for MCAT hormones.

However, with that said, these are the most frequent biology topics that show up on the MCAT—they’re not the only ones! For a full list of topics that you could see on this section of the test, check out Magoosh’s full list of MCAT topics.

MCAT Biochemistry Topics

25% of the Biological and Biochemical Foundations of Living Systems focus on biochemistry. Specifically, on topics you’d learn in a first-semester biochemistry class. So, with that in mind, what do you need to study?

You’ll need to know the building blocks of biochemistry, first of all. Think: amino acids, peptides, proteins, nucleic acids, nucleases, and the Watson-Crick model. After that, focus on areas including:

  1. Enzymes, including structure, function, and plotting enzyme inhibition;
  2. Other macros, including bioenergetics, lipids (structures, functions, and metabolism), carbohydrates (structure and metabolism), and the regulation and integration of metabolism;
  3. Metabolic pathways, including glycolysis and pentose phosphate, the citric acid cycle, ETC and oxidative phosphorylation, and biosignaling;
  4. Separations and purifications, including paper chromatography and TLC, column chromatography, electrophoresis and IEF, and Southern blot.

Again, this list is not exhaustive, so I highly recommend checking out the full MCAT topics page. However, this is a great place to start for the most commonly tested biochemistry topics! The AAMC content outlines are also excellent resources.

How to Study for MCAT Biology/Biochemistry

Now that you understand what topics should be your main priority for an MCAT biochemistry/MCAT Biology review, here are some principles of studying for the MCAT that apply to all sections. One is to start early and come up with a study plan. The earlier you start, the more time you will have to identify weaknesses and improve on them. Another is to study hard in the prerequisite classes for medical school—in this case, cellular and molecular biology and biochemistry. No MCAT prep course or tutor will go into as much depth as a college-level course in these subjects. Review courses and prep courses are meant to be review for concepts you have already learned. The better you do in your basic science courses and the better you learn the topics taught in them, the better you will do in both your MCAT and your medical school application.

Beyond that, it’s important to think about how the MCAT assesses biology and biochemistry compared to other parts of the test. In general, the biology and biochemistry questions on the MCAT emphasize memorization of different functions and facts. You’ll want to make sure that you’ve got a solid understanding of biological systems and foundations for the MCAT.

MCAT Biology/Biochemistry Study Methods

As you practice with MCAT biology and biochemistry passages, it’s crucial that you approach them in an efficient manner. It’s probably pretty clear right now that this isn’t reading that you would do for fun; this is reading for a specific purpose. You’re not only going to use your scientific inquiry skills, but you’re also going to use scientific reasoning skills. With that in mind, here are a few pointers to practice as you read passages in this section and start doing practice problems associated with passages:

  • Annotate as you read. Jot down crucial information, like the main idea of each paragraph or term definitions, on your note board.
  • Don’t be afraid to draw! Visualizing what you’re reading about is important for understanding the information. By drawing it (quickly), along with your outline, you’ll be able to retain the information better—and refer back to it while answering MCAT Biology practice questions.
  • Keep the big picture in mind. As you read, question why the author included details and how they relate to the passage as a whole. Jotting down related ideas from your studies can also help you see this bigger picture as you read.

To succeed on passage questions, you’ll need to have both an overall understanding of the main ideas of the passage itself, as well as a specific understanding of the details and concepts included in it. These practices will help you get there!

MCAT Biology/Biochemistry Study Priorities

As you start your MCAT prep, focusing on the above areas of biology and biochemistry will help you focus on the most commonly tested topics on the test. However, as you go further in your studies and start completing full-length practice tests, we highly recommend using the MCAT topics PDF as a checklist for your bio/biochem content review. This will ensure that you cover anything you might see on the exam before test day—including in other sections that also test biology (both the Chemical and Physical Foundations of Biological Systems and the Psychological, Sociological section and the Biological Foundations of Behavior section test a small amount of biology, as well). Good luck!

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  • Kat Thomson

    Kat is the Senior Curriculum Manager at Magoosh with a specialty in the MCAT. She has a BA from the University of California, Santa Barbara, and a Ph.D. in medical sociology from the University of California, San Francisco, where she earned the Distinguished Dissertation Award in the Social and Behavioral Sciences. Kat has been teaching premed and nursing students since 2005 as a Visiting Assistant Professor at the University of San Francisco, Bowdoin, and the University of California, Berkeley, while collaborating on multiple research projects and publications. In addition to the MCAT, Kat has taught courses in Research Methods, Gender, Global and Environmental Health, and others. She is passionate about increasing the number of underrepresented minorities in medicine and helping students get into the medical schools of their dreams. You can join Kat on Instagram and YouTube.