What’s Tested on the MCAT: Biology

The Biological and Biochemical Foundations of Living Systems section of the MCAT, often called the MCAT Biology or MCAT Bio/Biochem section for short, requires you to solve problems based on knowledge of biological and biochemical concepts combined with Scientific Inquiry and Reasoning Skills. The content on this section of the test also includes some general chemistry and organic chemistry.

However, you should keep in mind that the MCAT requires more than just an understanding of science content. The MCAT is first and foremost a test of critical reasoning skills. Knowing how to use biology and biochemistry information to interpret and solve more difficult problems is the key to a great MCAT score.

Without the foundational content, it is difficult to do well on the MCAT. As the official MCAT® prep of the American Medical Student Association, here are Kaplan’s recommendations for what to know for the Bio/Biochem section of the MCAT.

The undergraduate courses that are reflected in the Bio/Biochem section of the MCAT are:

• Introductory Biology (65%)
• First-semester Biochemistry (25%)
• Introductory General Chemistry (5%)
• Introductory Organic Chemistry (5%)  

In order to study effectively for the MCAT Biological and Biochemical Foundations of Living Systems section, you should thoroughly understanding these biology topics:

• Cardiovascular Systems
• Cells
• Digestive Systems
• Embryogenesis and Development
• Endocrine Systems
• Excretory Systems
• Genetics and Evolution
• Immune Systems
• Nervous Systems
• Musculoskeletal Systems
• Reproduction
• Respiratory Systems

In order to study effectively for the MCAT Biological and Biochemical Foundations of Living Systems section, you should thoroughly understanding these biochemistry topics:

• Amino Acids, Peptides, and Proteins
• Biological membranes
• Carbohydrate metabolism
• Carbohydrate structure
• DNA and RNA
• Enzymes
• Lipids and lipid metabolism
• Non-enzymatic proteins
• Regulation of metabolism

You’ll also need to be familiar with what’s tested on the Chemical and Physical Foundations of Biological Systems section of the MCAT.

The critical reasoning skills required for the MCAT have been defined by the AAMC as Scientific Reasoning and Inquiry Skills, or SIRS.

These skills are tested in all three of the science sections of the MCAT (Chemical and Physical Foundations of Biological Systems, Biological and Biochemical Foundations of Living Systems, and Psychological, Social and Biological Foundations of Behavior).

The MCAT will present you with 10 passages on biology and biochemistry topics, and ask 4-7 questions about each passage. The questions will address the four skills listed, although not every passage will require you to use each skill. You will also be presented with 15 discrete questions that are not associated with passages. These will also be designed to test both your science knowledge and application of that knowledge based on these four skills.

The bio/biochem section of the MCAT is scored on a scale of 118-132, with the median score of all test takers set to be 125. A given scaled score does not correspond to any specific number of right or wrong questions. According to the AAMC, “The MCAT exam is not graded on a curve. Instead, the MCAT exam is scaled and equated so that scores have the same meaning, no matter when you test or who tests at the same time you did.” The score for this section of the test is combined with the other three sections to provide your overall score which ranges from 472 to 528.

[ RELATED: What’s a Good MCAT Score? ]

The biological and biochemical foundations of living systems section of the MCAT is the third section to be tested and follows a thirty-minute lunch break.

Biological and Biochemical Foundations of Living Systems section
Length	95 minutes
Format	59 questions
	10 passages
	44 passage-based questions
	15 discrete (non-passage based) questions
Score	Between 118 and 132
Topics tested	Biochemistry: 25%
	Biology: 65%
	General Chemistry: 5%
	Organic Chemistry: 5%

[ RELATED: MCAT Test Day Schedule ]

The AAMC has described the topics within the Biological and Biochemical Foundations of Living Systems section of the MCAT. These topics are subdivided into three Foundational Concepts, each of which has several sub-categories.

You can also visit the AAMC site to learn more about the construction of the MCAT.

[ RELATED: MCAT Psychological, Social, and Biological Foundations of Behavior Section ]

This topic is further subdivided into four categories:

• Structure and function of proteins and their constituent amino acids
• Transmission of genetic information from the gene to the protein
• Transmission of heritable information from generation to generation and the processes that increase genetic diversity
• Principles of bioenergetics and fuel molecule metabolism

This topic is about the interaction of highly-organized assemblies of molecules, cells and organs to carry out the functions of living organisms. This topic is further subdivided into three categories:

• Assemblies of molecules, cells and groups of cells within single cellular and multicellular organisms
• The structure, growth, physiology, and genetics of prokaryotes and viruses
• Processes of cell division, differentiation and specialization

[ RELATED: All MCAT Exam Sections and Subjects ]

This topic is about the integrated functioning of complex systems of tissues and organs to sense internal and external environments of multicellular organisms and to maintain a stable internal environment within an ever changing external environment. This is further subdivided into two subcategories:

• Structure and function of the nervous and endocrine systems and ways in which these systems coordinate organ systems
• Structure and integrative function of the main organ systems