PA-CAT Test Sections and Number of Questions: The Core Five
Section 1: Biology & Biochemistry (60 questions)
The PA-CAT biology questions represent the largest single block of the exam, emphasizing the biological life sciences that underpin human health. This section is weighted heavily because it directly correlates with the didactic year of PA school, where students must master pathophysiology and pharmacology. Candidates are expected to navigate complex systems, from the micro-level of mitochondrial function to the macro-level of organ system integration. The inclusion of biochemistry necessitates a working knowledge of metabolic pathways, enzymatic kinetics, and the thermodynamic laws governing biological reactions. Because these 60 questions form 25% of the total exam, proficiency here is non-negotiable for a high composite score.
Section 2: Chemistry & Physics (60 questions)
The PA-CAT chemistry section is integrated with physics to assess a candidate's grasp of the physical laws of the universe and their application to chemical systems. This 60-question block covers general chemistry, organic chemistry, and introductory physics. The exam focuses on concepts such as stoichiometry, acid-base equilibrium, and functional group reactivity. Physics questions often lean toward mechanics and fluids, mirroring the pressures and flows found in human hemodynamics. Success in this section requires the ability to transition quickly between abstract physical laws and concrete chemical reactions, reflecting the multidisciplinary nature of medical science.
Section 3: Critical Reading & Reasoning (40 questions)
PA-CAT critical reading content departs from pure science to evaluate a candidate’s literacy and analytical capabilities. This 40-question section presents passages that require high-level synthesis and evaluation. Unlike simple reading comprehension, critical reasoning asks you to identify underlying assumptions, evaluate the strength of evidence, and determine the logical implications of a text. In a clinical setting, PAs must interpret complex research and patient histories; this section mirrors that demand by testing your ability to extract meaning from dense, often unfamiliar, academic or ethical prose. It is a test of cognitive agility rather than rote memorization.
Section 4: Mathematics (40 questions)
PA-CAT math topics focus on the quantitative skills necessary for evidence-based practice and clinical calculations. Comprising 40 questions, this section avoids high-level calculus in favor of algebra, statistics, and probability. You will encounter problems involving dosage calculations, interpreting statistical significance in medical research (such as p-values and confidence intervals), and analyzing data sets. The scoring system rewards accuracy in quantitative reasoning, as these skills are vital for avoiding medication errors and understanding epidemiological trends. Candidates must be comfortable with mental math and quick estimation to maintain the required pace.
Section 5: Psychology & Sociology (40 questions)
The PA-CAT psychology sociology breakdown includes 40 questions that address the "human" side of medicine. This section recognizes that patient outcomes are often dictated by behavioral, social, and cultural factors. Topics range from developmental psychology to the sociological determinants of health. By testing these disciplines, the PA-CAT aligns with the holistic approach of the PA profession. Candidates must understand theories of behavior change, the impact of socioeconomic status on healthcare access, and the psychological basis of patient-provider interactions. This section ensures that applicants possess the empathy and social awareness required for effective patient advocacy.
Deep Dive: Biology and Biochemistry Content
Cellular and Molecular Biology Focus
At the heart of the biology section is a rigorous examination of cellular mechanics. Candidates must demonstrate mastery of the Central Dogma of molecular biology: the process by which DNA is transcribed into RNA and translated into proteins. This involves understanding the specific roles of RNA polymerase, ribosomes, and post-translational modifications. Questions often delve into the cell cycle, requiring knowledge of the checkpoints (G1, S, G2, and M) and the regulatory proteins, such as cyclins and tumor suppressors, that prevent oncogenesis.
Furthermore, the exam tests the intricacies of cellular respiration. You should be prepared to calculate the ATP yield from a single molecule of glucose through glycolysis, the Krebs cycle, and the electron transport chain. Understanding the electrochemical gradient across the inner mitochondrial membrane is a common assessment point. This molecular foundation is critical because it explains the mechanism of action for many pharmaceutical agents that PA students will later study in detail.
Human Anatomy and Physiology Topics
The PA-CAT moves from the cellular level to systemic physiology, focusing on the major organ systems: cardiovascular, respiratory, renal, endocrine, and nervous systems. In the realm of anatomy, the focus is less on naming every bone and more on the relationship between structure and function. For example, a question might ask about the physiological consequences of a valve defect in the heart, requiring knowledge of blood flow through the atria and ventricles.
Physiology questions often utilize the concept of Homeostasis and negative feedback loops. You might be asked to predict the hormonal response to a sudden drop in blood pressure, involving the Renin-Angiotensin-Aldosterone System (RAAS). This requires an integrated understanding of how the kidneys, lungs, and adrenal glands communicate. Mastery of these topics is essential, as the PA-CAT uses these questions to simulate the diagnostic reasoning processes used by clinicians to identify systemic imbalances in patients.
Deep Dive: Chemistry, Physics, and Mathematics Content
General and Organic Chemistry Emphasis
The chemistry portion of the exam balances the quantitative nature of general chemistry with the structural complexity of organic chemistry. In general chemistry, candidates must be proficient in Le Chatelier’s Principle, predicting how shifts in concentration, temperature, or pressure affect chemical equilibrium. This concept is vital for understanding blood pH buffering systems, such as the bicarbonate buffer. You will also encounter questions on thermodynamics (Enthalpy and Entropy) and the behavior of ideal gases.
Organic chemistry questions focus on the properties and reactions of functional groups, such as alcohols, amines, and carboxylic acids. A key area of assessment is stereochemistry; understanding the difference between enantiomers and diastereomers is crucial, as the biological activity of drugs often depends on their specific 3D orientation. You should be familiar with nucleophilic substitution (Sn1/Sn2) and elimination (E1/E2) mechanisms. These concepts are fundamental to understanding how the body metabolizes xenobiotics and how various drugs interact at the molecular level.
Physics Principles and Math Application
Physics on the PA-CAT is applied rather than theoretical. It focuses on the principles that govern the physical body and medical technology. Poiseuille's Law, which describes the flow of fluids through a pipe (or blood through a vessel), is a frequent topic. Candidates must understand how changing the radius of a vessel dramatically impacts resistance and flow rate. Other topics include optics—essential for understanding how the human eye focuses light—and wave mechanics, which relates to ultrasound technology and hearing.
In the mathematics subsection, the emphasis is on "word problems" that require the application of algebraic formulas to real-world scenarios. You will need to calculate percentages, ratios, and proportions quickly. A significant portion of the math section is dedicated to descriptive and inferential statistics. You must be able to distinguish between mean, median, and mode, and understand the implications of standard deviation in a normal distribution. This quantitative literacy is what allows a PA to interpret a lab report or a clinical trial result accurately.
Deep Dive: Critical Reading and Behavioral Sciences
Analyzing Scientific and Ethical Passages
The Critical Reading and Reasoning section tests your ability to deconstruct arguments. The passages provided are often dense and academic, covering topics such as bioethics, medical history, or recent scientific discoveries. You are not tested on your prior knowledge of the topic, but on your ability to perform Logical Inference. For example, a passage might present a new theory on neuroplasticity, and the questions will ask you to identify which piece of evidence, if true, would most weaken the author’s conclusion.
This section also evaluates your understanding of rhetorical structure and tone. Is the author being objective, or is there an inherent bias? In the healthcare field, the ability to read between the lines of a medical journal article or an ethical debate is paramount. The scoring for this section looks for "evaluative" thinking—the ability to look at a text and determine its validity based solely on the logic presented. This skill is a prerequisite for the evidence-based medicine (EBM) framework used in PA education.
Key Psychology and Sociology Theories
In the behavioral science section, the PA-CAT assesses your knowledge of foundational theories that explain human behavior and societal structures. You will encounter questions on Classical and Operant Conditioning, which are essential for understanding patient habits and adherence to treatment plans. Developmental theories, such as those by Piaget or Erikson, are also tested to ensure you understand the cognitive and emotional milestones of patients across the lifespan.
Sociological concepts focus on the "Social Determinants of Health." You should be familiar with terms like social stratification, institutional racism, and the "sick role." The exam asks how these factors contribute to health disparities and how a provider’s awareness of their own implicit biases can improve patient outcomes. By mastering these theories, you demonstrate a readiness to treat patients not just as biological entities, but as individuals existing within a complex social context. This section is a critical component of the PA-CAT content distribution, highlighting the profession's commitment to comprehensive care.
Time Management Based on Section Length
Allocating Minutes Per Question
With 240 questions and a 270-minute total testing time (including breaks), managing your pace is as important as knowing the material. On average, you have approximately 60 to 70 seconds per question, depending on how you utilize your break time. However, not all questions are created equal. Science questions involving complex calculations or multi-step organic chemistry mechanisms may take 90 seconds, while a psychology definition might take only 30.
Developing a Pacing Strategy is essential. For the 60-question science blocks, aim to reach the halfway point (question 30) by the 30-minute mark. This leaves a buffer for the more difficult questions at the end of the section. In the Critical Reading section, the challenge is different; you must balance the time spent reading the passage with the time spent answering the 40 questions. A common mistake is spending too much time on the text and rushing the questions, which often contain subtle distractors that require careful thought to eliminate.
Prioritizing High-Question-Count Sections in Study
Given that Biology & Biochemistry and Chemistry & Physics account for 120 of the 240 questions, your study schedule should reflect this 50% weighting. These sections are not only the most populous but also the most cognitively demanding due to the breadth of the material. If you are a month away from the exam, your "high-yield" focus should be on these two science pillars.
Exam Tip: Use a "triage" method during the test. If a question in a high-count section seems unsolvable within 90 seconds, mark it and move on. Every question carries the same weight toward your raw score, and you cannot afford to miss five easy questions because you were stuck on one difficult stoichiometry problem.
Prioritization also means identifying your "weakest high-yield" area. If you are strong in Biology but struggle with the PA-CAT chemistry section, your study hours should be skewed toward chemistry to maximize the potential for score improvement in a high-impact area.
Creating a Study Schedule Mirroring the Test Blueprint
An effective study plan should be a mirror image of the PA-CAT blueprint. If the exam is 25% Biology, 25% Chemistry/Physics, and 16.6% each for the remaining three sections, your weekly study hours should follow a similar ratio. For a 20-hour study week, this translates to 5 hours of Biology, 5 hours of Chemistry/Physics, and roughly 3.3 hours each for Math, Reading, and Behavioral Sciences.
This method ensures that you do not over-study "comfort" subjects while neglecting the PA-CAT psychology sociology breakdown or math topics. Use a Diagnostic Assessment early in your preparation to identify which specific topics within these sections require the most attention. For instance, if your diagnostic shows you are proficient in anatomy but weak in biochemistry, redistribute your "Biology" hours to favor metabolic pathways. This data-driven approach prevents study plateaus and ensures that every hour spent contributes to a higher composite score.
Focusing Resources on High-Weight Content Areas
When selecting study materials, prioritize those that offer high-volume practice in the two 60-question blocks. Success on the PA-CAT is often a matter of pattern recognition—the more PA-CAT biology questions you see, the faster you will recognize the "distractor" answers designed to trip up unprepared candidates.
Focusing resources also means understanding the "depth" required for each section. The PA-CAT is an "inch deep and a mile wide" for some subjects, but very deep for others like physiology and organic chemistry. Invest in resources that provide detailed rationales for every practice question. Understanding why an answer is wrong is often more educational than knowing why one is right, as it reinforces the underlying scientific principles. By aligning your resources with the exam's structure, you build the stamina and mental flexibility needed to transition between disparate subjects on test day, ultimately securing your place in a competitive Physician Assistant program.