MCAT Biology & Biochemistry

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MCAT Biology Review

The MCAT's Biological and Biochemical Foundations of Living Systems section assesses your knowledge and application of basic science concepts.

MCAT Biology questions combine general knowledge with scientific inquiry. You need undergraduate-level knowledge of biology and chemistry as well as critical reasoning and deductive skills to examine data, make inferences and draw meaningful conclusions.

Exam Structure

How Many Passages Are in the MCAT Biology Section?

The Biology and Biochem portion of the MCAT contains 59 multiple-choice problems including ten reading passages with 44 related questions. The remaining 15 questions require specific content knowledge to answer correctly.

The time limit is 95 minutes, and test-takers have access to the periodic table of elements during this section.

Skills Evaluated

Knowledge, Scientific Inquiry & Reasoning

The MCAT measures how you apply critical thinking, scientific reasoning, and research methodology to different topics in three sections of the exam, including Biochem and Biology. In other words, you need a combination of content knowledge and four specific reasoning skills as defined by the AAMC.

  • Knowledge of Scientific Concepts and Principles
  • Scientific Reasoning and Problem-Solving
  • Reasoning about the Design and Execution of Research
  • Data-based and Statistical Reasoning

Section Content

What Biology Is on the MCAT?

This section covers introductory-level biology and biochemistry, as well as inorganic and organic chemistry. Beyond knowing the basics of genetics, anatomy, metabolism, and chemistry, you'll need an in-depth understanding of how molecules, cells, and organs behave and interact to answer MCAT biology questions.

Biology vs. Biochem

Is General Biology on the MCAT?

Introductory biology content appears in roughly 65% of this section. To prepare accordingly, test-takers should review the following topics:

  • Organ systems of the human body
  • Cells
  • Embryogenesis and Development
  • Genetics and Evolution
  • Reproduction

What's the Percentage of Biochem on the MCAT?

Biochemistry factors into roughly 25% of the MCAT's Biology section. To prepare, you'll need to know core concepts related to DNA and RNA functions and mutations, the structure of enzymes, amino acids, and proteins, and metabolic pathways.

Should I Study Chemistry for this Section?

About 10% of the MCAT Biology section includes organic and inorganic chemistry. Fortunately, the same basic concepts and skills needed for Chemical and Physical Foundations of Living Systems apply to this section as well.

Exam Prep

How Do I Do Well on the MCAT Biology Section?

The MCAT is a difficult test, but you can master the toughest questions with enough preparation. An effective, realistic MCAT study plan can significantly improve your medical school exam scores. Consider the tips below when developing your study schedule:

  • Take a practice exam: Test your knowledge with some MCAT biology practice questions to get a sense of what you need to study.
  • Use a study program: Once you know what to expect on the exam, find an online MCAT prep course to help you streamline your strategy.
  • Create a routine: Avoid cramming and burnout by developing an MCAT Biology study guide that lets you work at a steady pace.

Study Resources

Online MCAT Test Prep

MCAT Sections

Exam Difficulty

How to Study for the MCAT