What's on the MCAT: Subjects & Content Areas
A thorough breakdown of every subject, skill, and question type across all four scored sections of the MCAT exam.
More Than Memorization — The MCAT Tests How You Think
The MCAT does not simply quiz you on isolated facts. The AAMC designed this exam to measure two distinct dimensions: your command of foundational concepts in the natural and social sciences, and your ability to apply scientific reasoning and critical analysis skills under timed conditions.
Most questions are embedded within passages — short excerpts from research studies, experiments, or scholarly arguments — that require you to interpret data, evaluate hypotheses, and synthesize information across disciplines. A smaller number of standalone (discrete) questions test core knowledge directly.
Passage-Based vs. Discrete Questions
Understanding how questions are delivered is just as important as knowing the content itself. The MCAT uses two primary formats across its science sections.
Passage-Based Questions
Each passage is typically 300–600 words long and presents an experimental scenario, a set of research findings, or a theoretical discussion. You will then answer 4–7 multiple-choice questions that require you to analyze the passage, apply outside knowledge, and draw logical conclusions. Approximately 75–80% of the science section questions follow this format.
Discrete (Standalone) Questions
These freestanding questions appear independently of any passage. They test your recall of specific principles, your ability to perform quick calculations, or your understanding of a concept in isolation. Approximately 20–25% of each science section's questions are discrete. CARS, by contrast, is entirely passage-based with no discrete questions.
What Each MCAT Section Covers
Below is a detailed look at the subjects, foundational concepts, and scientific inquiry skills tested in each of the four scored sections.
Chemical & Physical Foundations of Biological Systems
59 questions | 95 minutes | Score: 118–132
This section evaluates your grasp of how chemical and physical processes underpin biological systems. You will encounter topics from general chemistry (atomic structure, bonding, thermodynamics, kinetics, equilibrium, acids and bases, electrochemistry), organic chemistry (functional groups, reaction mechanisms, stereochemistry, spectroscopy), physics (mechanics, fluids, electrostatics, circuits, optics, waves), and introductory biochemistry (amino acids, protein structure, enzyme kinetics).
The AAMC organizes this section around Foundational Concepts 4 and 5, which focus on the physical principles governing living systems and the chemical interactions that sustain life.
Full Chem/Phys Guide
Critical Analysis & Reasoning Skills (CARS)
53 questions | 90 minutes | Score: 118–132
CARS is entirely passage-based and draws from the humanities, philosophy, ethics, cultural studies, and social sciences. No scientific knowledge is needed — instead, the section measures your capacity to comprehend complex arguments, identify unstated assumptions, evaluate the strength of evidence, and extend an author's reasoning to new scenarios.
Questions fall into three skill categories: Foundations of Comprehension (understanding what is explicitly stated), Reasoning Within the Text (making inferences from the passage), and Reasoning Beyond the Text (applying ideas to novel contexts).
Full CARS Guide
Biological & Biochemical Foundations of Living Systems
59 questions | 95 minutes | Score: 118–132
This is the most biology-heavy section on the exam. You will be tested on cell biology, molecular biology, genetics, evolution, organ system physiology, biochemistry (enzyme regulation, metabolic pathways, bioenergetics), and introductory organic and general chemistry as they relate to biological processes.
The AAMC maps this section to Foundational Concepts 1, 2, and 3, which address biomolecules, cellular processes, organ systems, and the transmission of genetic information.
Full Bio/Biochem Guide
Psychological, Social & Biological Foundations of Behavior
59 questions | 90 minutes | Score: 118–132
The newest addition to the MCAT, this section examines how psychological, sociocultural, and biological factors influence perception, behavior, and health outcomes. Key disciplines include introductory psychology (cognition, learning, memory, motivation, emotion, development, personality, psychological disorders), sociology (social stratification, institutions, demographics, inequality), and biology (the nervous system, endocrine system, and their effects on behavior).
Content is organized under Foundational Concepts 6, 7, 8, 9, and 10, spanning everything from sensory processing to social determinants of health.
Full Psych/Soc GuideFoundational Concepts & Scientific Inquiry Skills
The AAMC structures the MCAT around 10 Foundational Concepts and 4 Scientific Inquiry and Reasoning Skills. Understanding this framework helps you study more strategically.
10 Foundational Concepts
These are the broad content themes the AAMC expects you to master. Concepts 1–3 correspond to Bio/Biochem, Concepts 4–5 to Chem/Phys, and Concepts 6–10 to Psych/Soc. Each concept is further divided into content categories and specific topic lists that serve as your content blueprint for studying.
4 Scientific Inquiry & Reasoning Skills
Regardless of section, every MCAT question also targets one of four skill levels: Skill 1 — Knowledge of scientific principles; Skill 2 — Scientific reasoning and problem-solving; Skill 3 — Reasoning about the design and execution of research; Skill 4 — Data-based and statistical reasoning. Skills 1 and 2 account for the majority of questions.
How Dr. Donnelly Approaches MCAT Content Mastery
Knowing what is tested is the first step. Knowing how to study it efficiently is what separates average scores from outstanding ones.
Targeted Gap Analysis
Dr. Donnelly begins every tutoring engagement with a diagnostic evaluation to pinpoint exactly which foundational concepts and skills you need to strengthen — so you never waste time reviewing material you already command.
Integrated Subject Practice
Because MCAT passages frequently blend multiple disciplines, Stuart trains you to think across subject boundaries — connecting biochemistry to cell biology, or physics to organ-system physiology — just as the exam demands.
Passage-First Methodology
Rather than drilling facts in isolation, Dr. Donnelly immerses you in passage-based practice from day one. This builds the analytical stamina and speed that the MCAT rewards far more than pure memorization.
Want a Personalized MCAT Content Plan?
Book a free consultation with Dr. Donnelly. He will evaluate your strengths and weaknesses across all four sections and design a study roadmap tailored to your target score.
