Top 200 Vocabulary Word List for the MCAT | Must Know Words for Common Examination Instructions

The 200-word examination instruction list

MCAT question instructions tell you whether to interpret a passage, apply a scientific principle or judge how a study supports a conclusion. The word except reverses the selection rule. In Critical Analysis and Reasoning Skills, the task and passage provide the information you need to answer.

The numbered bank combines question directions, answer-format phrases and terms that help you work with the task. Use the official instructions for the exact item and test cycle.

Exam requirements · Worked examples · Fencing Method

MCAT sections, question stems and experimental comparisons

No.	Instruction or term	What it asks you to do
1	Chemical and Physical Foundations	Apply chemistry and physics to the biological system and data described.
2	Critical Analysis and Reasoning Skills	Use the supplied passage and question to interpret ideas and arguments.
3	Biological and Biochemical Foundations	Connect molecular, cellular or organism-level concepts to the evidence supplied.
4	Psychological, Social, and Biological Foundations	Apply behavioural and social science concepts within the stated scenario.
5	Passage-based question	Use the passage, question stem and relevant concepts together as the section requires.
6	Discrete question	Answer the stand-alone prompt using the information supplied and required knowledge.
7	Foundations of Comprehension	Identify stated ideas, relationships and the passage’s structure.
8	Reasoning Within the Text	Connect parts of the passage to interpret or assess its reasoning.
9	Reasoning Beyond the Text	Apply the passage’s ideas to new information given in the question.
10	Scientific Reasoning and Problem Solving	Use the relevant principle to explain or predict the outcome in context.
11	Reasoning about Research Design	Judge the design, procedures and conclusions of the described study.
12	Data-Based and Statistical Reasoning	Use the relevant figures and statistical meaning before drawing a conclusion.
13	Best explanation	Choose the mechanism that most directly accounts for the specified result.
14	Most consistent with the results	Choose the interpretation that fits the reported evidence.
15	Least likely	Select the option with the weakest fit to the given conditions.
16	Except	Find the choice that fails the rule the other options meet.
17	Based on the passage alone	Use the evidence and reasoning provided in the passage rather than outside facts.
18	According to the author	Use the position the author actually takes.
19	New information	Apply the added fact to the existing argument or model without rewriting the original facts.
20	Model prediction	Find what the proposed explanation would lead you to expect under the stated conditions.
21	Effect of inhibition	Use the named target and pathway to predict what changes when its activity is reduced.
22	Mechanism of action	Identify the steps by which the named factor produces the stated result.
23	Wild-type group	Use the unmodified reference group for the comparison described.
24	Knockout group	Read what changes when the specified gene has been inactivated or removed.
25	Vehicle control	Compare with the group receiving the delivery medium without the active agent.
26	Positive control	Use the comparison expected to show that the procedure can detect an effect.
27	Negative control	Use the comparison expected to show what happens without the target effect.
28	Baseline measurement	Use the reading taken before the stated intervention or change.
29	Normalise to	Compare measurements relative to the specified reference or starting value.
30	Fold change	Divide the later or treatment value by the comparison value as the item defines it.

Measurement, research design and result wording

No.	Instruction or term	What it asks you to do
31	Dose response	Read how the outcome changes as the amount of the treatment changes.
32	Time course	Track the outcome at the relevant times after the event or treatment.
33	Experimental readout	Identify what the reported measurement actually indicates.
34	Assay	Identify the procedure measuring the stated substance, activity or outcome.
35	Specificity	Check whether the method or effect distinguishes the intended target from alternatives.
36	Affinity	Interpret the relative tendency of the specified molecules to bind under the conditions described.
37	Direction of change	State or select whether the result increases, decreases or remains similar.
38	Magnitude	Consider how large the change is in the requested units.
39	Approximate calculation	Use values and rounding that distinguish the available answers.
40	Dimensional analysis	Track units through the calculation to see whether the result has the requested dimension.
41	Order of magnitude	Estimate the relevant power-of-ten scale.
42	Direct relationship	Check whether both quantities change in the same direction under the stated model.
43	Inverse relationship	Check whether an increase in one quantity accompanies a decrease in the other.
44	Cohort	Identify the group followed or compared in the study.
45	Cross-sectional comparison	Read the differences measured at the stated time without assuming a later causal sequence.
46	Experimental manipulation	Identify what investigators deliberately changed.
47	Operational definition	Use the measurable rule the study gives for the concept.
48	Selection bias	Check whether the way participants were included affects the comparison.
49	Social context	Use the group, setting or institution specified in the question.
50	Alternative hypothesis	Identify a different explanation or prediction the study could test.
51	Control for	Account for a factor that could otherwise distort the comparison.
52	Statistically significant	Interpret the result under the test and threshold supplied, alongside the effect and uncertainty.

Scientific evidence, graphs and passage reasoning

No.	Instruction or term	What it asks you to do
53	Identify the reference group	Find the comparison used to isolate the change attributed to the intervention.
54	Predict the outcome	State the expected result in the conditions described.
55	Justify your prediction	Connect your proposed outcome to a mechanism or evidence that makes it plausible.
56	Identify the independent variable	Name the factor manipulated or selected as input.
57	Identify the dependent variable	Name the outcome that was measured.
58	Sample mean	Use the average of the values in the specified sample.
59	Standard error	Interpret it as uncertainty in an estimated statistic where the question uses that measure.
60	Error bars	Read their meaning from the figure legend before interpreting them.
61	Control treatment	Use the treatment intended to provide a reference comparison.
62	Support the claim	Give evidence that bears on the exact claim in the question.
63	Explain the result	Connect the observation to a biological, historical or other applicable reason.
64	Experimental design	Use the stated groups, conditions and measurements to judge the experiment.
65	Sample size	Check how many observations or individuals contribute to the result.
66	Repeat the trial	Run the same test again to investigate variation or consistency.
67	Controlled variable	Identify a factor kept constant to help isolate the tested relationship.
68	Raw data	Use the measurements as originally collected.
69	Processed data	Use values calculated, combined or transformed from the original readings.
70	Uncertainty	State or interpret the estimated doubt associated with a measurement or value.
71	Absolute uncertainty	Express the estimated uncertainty in the same units as the quantity.
72	Percentage uncertainty	Express the uncertainty relative to the measured value as a percentage.
73	Outlier	Identify an observation unusually far from the general pattern.
74	Anomalous result	Recognise a result inconsistent with the main pattern or expected relationship.
75	Reliability	Consider whether a result or method gives consistent findings.
76	Validity	Consider whether the evidence or method answers the intended question.
77	Resolution	Identify the smallest change that the device or scale can display.
78	Repeatability	Consider agreement when the same method is repeated under the same conditions.
79	Reproducibility	Consider whether results agree when the method is repeated under changed conditions.
80	Limitations	Identify specific boundaries on the conclusions that the method can support.
81	Strengths	Explain features that make the evidence or method fit the purpose.
82	Correlation	Describe how variables vary together within the data.
83	Causation	Explain how one factor produces a change in another when evidence supports it.
84	Confounding factor	Identify a factor that could contribute to the apparent relationship.
85	Representative sample	Check whether the selected cases reflect the population of interest.
86	Model	Use a simplified mathematical or conceptual representation to address the task.
87	Parameter	Identify a quantity that sets a feature of the model.
88	Domain	Give the set of allowed input values in the context.
89	Interpolate	Estimate within the range covered by the data.
90	Extrapolate	Estimate outside the observed range using an assumed pattern.
91	Fit	Judge how closely a model agrees with the data.
92	Residual	Find the observed value minus the model’s predicted value.
93	Rate of change	Find the change in one quantity per unit change in another.
94	Approximation	Give a suitably rounded or estimated value.
95	Significant figures	Give the requested number of meaningful digits.
96	Deductive reasoning	Show how a conclusion follows from premises or prior results.
97	Counterexample	Give one valid case that disproves a general claim.
98	Counterclaim	Present a plausible position that challenges the claim.
99	Alternative cause	Identify another event that could produce the observed result.
100	Causal chain	Track the sequence of proposed causes and check which links have support.
101	Causal inference	Decide whether the evidence supports a causal claim or only an association.
102	Normative claim	Recognise a claim about what ought to happen.
103	Descriptive claim	Recognise a claim about what happens or has happened.
104	Underlying principle	State the general rule connecting the argument’s evidence and conclusion.
105	Analogous case	Find a comparable case that preserves the relevant relationship.
106	Main conclusion	Identify the claim that the rest of the reasoning ultimately supports.
107	Intermediate conclusion	Identify a claim that receives support and then helps support a further claim.
108	Support gap	Find the step that is assumed between the premises and conclusion.
109	Degree of certainty	Distinguish proof, likelihood and possibility in the wording of a conclusion.
110	Blind analysis	Check whether the person measuring or analysing outcomes knew the group assignment.
111	Complete the argument	Choose the conclusion or missing proposition that follows from the stated reasoning.
112	Sufficient information	Decide whether the facts supplied establish one required conclusion.
113	Consider both positions	Check what each speaker claims about the same proposition.
114	Opposite outcome	Check which observation would run against the model’s prediction.
115	Interpretation of findings	Choose a conclusion that fits the measurements and the study design.
116	Consider a challenge	Address a serious objection or case that might weaken your position.
117	Reason and example	Show how the example demonstrates the point made by the reason.
118	Question stem	Read the wording that identifies the relationship between the evidence and the required choice.
119	Reasoning flaw	Locate the exact step where the evidence fails to support the conclusion.
120	Alternative explanation	Consider a different reason that could account for the same observation.
121	Author’s assumption	Identify a premise the argument relies on without stating directly.
122	Strength of support	Judge how directly a detail bears on the exact claim.
123	Best illustrates	Choose the example or quotation that most directly shows the idea.
124	Most directly supports	Pick the evidence with the clearest connection to the named claim.
125	If true	Assume the answer choice is true while judging its effect on the claim.
126	Function of a sentence	Identify how the sentence develops, limits or supports the passage’s argument.
127	Author’s claim	Find what the named author argues or asserts.
128	Point of agreement	Find what both sources would endorse based on the evidence.
129	Introduce	Choose wording that supplies the context needed for the stated audience.
130	Transitions	Identify the relationship between ideas before choosing a connecting expression.
131	Concession	Acknowledge a point before shifting to the principal claim.
132	Cause and effect	Choose a link that shows one event producing or explaining the other.
133	Quantifier	Watch for words such as all, some or none that alter a claim’s scope.
134	Textual evidence	Choose a detail from the source that supports the precise claim.
135	Scope	Check the population, time frame or range covered by the claim.
136	Strengthen	Identify information that makes the conclusion better supported.
137	Logical relationship	Identify whether adjacent ideas add, contrast, explain or exemplify.
138	Original research report	Use the methods and findings reported by the researchers when the passage supplies them.

Core instructions and evidence

No.	Instruction or term	What it asks you to do
139	Recognise	Find a familiar feature in a new example.
140	Identify	Name or pick out the item the question specifies.
141	Select	Choose only the number of options requested.
142	Match	Pair each item with the option that corresponds to it.
143	Complete	Fill in what is missing while keeping the supplied structure.
144	Label	Attach the correct name to the indicated part.
145	Locate	Find the specified detail, point or region.
146	Indicate	Make the chosen feature or answer clear.
147	Record	Write the result in the space and form provided.
148	Answer	Respond directly to the question being asked.
149	Give	Supply the requested fact, example or result.
150	State	Express the required point directly and clearly.
151	Name	Supply the correct term, person or item.
152	List	Set out the requested items separately.
153	Define	Give the precise meaning used in the subject or question.
154	Describe	Report the relevant characteristics, events or pattern.
155	Outline	Give the main steps or points in brief.
156	Summarise	Select the central points and leave out minor details.
157	Explain	Connect the result to its cause, mechanism or reasoning.
158	Compare	Set the items side by side on the same relevant feature.
159	Contrast	Show how the items differ on a shared point of comparison.
160	Analyse	Break down the evidence and explain how its parts relate.
161	Interpret	Say what a statement, result or display means in context.
162	Infer	Use clues to reach a conclusion the material implies.
163	Predict	Use available evidence to say what is likely to happen.
164	Suggest	Offer a plausible answer suited to the information given.
165	Justify	Give evidence for the claim and explain how that evidence supports, qualifies or defends it.
166	Evaluate	Weigh relevant evidence or criteria before reaching a judgment.
167	Assess	Judge the extent, value or strength of something using evidence.
168	Discuss	Develop a structured response that considers the relevant issues.
169	Distinguish	Give the feature that lets the reader tell two things apart.
170	Support	Supply evidence that helps establish the claim.
171	Illustrate	Make an idea clear with a relevant example or diagram.
172	Demonstrate	Show how a fact, process or result can be established.
173	Determine	Work from the given information to establish an answer.
174	Calculate	Use numbers or other given information to work out a result.
175	Estimate	Find an approximate answer using the available clues.
176	Check	Test the answer against the original instruction or condition.
177	Arrange	Put items into the order or grouping requested.
178	Sequence	Put stages into a meaningful order.
179	Classify	Assign each item to a category using the stated rule.
180	Group	Put items with a shared feature together.
181	Order	Sort items by the criterion given in the prompt.
182	Omit	Leave out the indicated item or detail.
183	Include	Make sure the requested part appears in the response.
184	Exclude	Keep the named item or category outside your answer.
185	Refer to	Use the specified passage, figure or notes when responding.
186	Based on	Ground the answer in the material named in the question.
187	According to	Use what the specified source says.
188	In context	Use the meaning that fits this passage or situation.
189	Most likely	Choose the conclusion with the strongest support among the options.
190	Best supported	Prefer the conclusion backed most directly by the evidence.
191	Explicit	Stated directly in the source.
192	Implicit	Suggested by the source and recoverable from clues.
193	Evidence	A fact, detail or observation that supports a claim.
194	Claim	An assertion that can be tested against evidence or reasoning.
195	Example	A particular case used to make a general idea clear.
196	Conclusion	The result reached after considering the reasoning or evidence.
197	Assumption	A premise taken as given for the purpose of the question.
198	Condition	A requirement that must be satisfied.
199	Constraint	A restriction that shapes the possible answers.
200	Criterion	A standard used to choose or judge an answer.

What the examination requires

Four multiple-choice sections

AAMC lists Chemical and Physical Foundations of Biological Systems, Critical Analysis and Reasoning Skills, Biological and Biochemical Foundations of Living Systems, and Psychological, Social, and Biological Foundations of Behavior. The three science and behavioural sections have 59 questions and 95 minutes each. CARS has 53 questions and 90 minutes.

Read science questions for the named comparison

Science and behavioural questions can be passage-based or stand-alone. A passage may give the method, a graph or a model. Identify the measured result and comparison group before deciding which outside concept is relevant. When a question names a particular result, separate that result from other data shown in the same display.

Treat CARS as a passage-reasoning task

AAMC’s overview says its passages and questions supply the information needed. Reasoning Within the Text can ask how ideas fit together. Reasoning Beyond the Text can give a new case or new information to test the passage’s ideas. Keep the author’s claim separate from a position that the author merely reports.

Use the format and admissions requirements that apply to you

The MCAT is a North American medical admissions exam administered internationally in selected locations. Consult AAMC for test-day procedures and the relevant institution for its admissions requirements. During practice, classify a miss by the job you misread, such as reverse selection, the wrong comparison or an inference stronger than the evidence.

• Read the whole instruction before choosing your first step.
• Identify the evidence, person, group or source named in the task.
• Check the response form and any stated limits.

Worked examples of common examination instructions

These original practice examples show how a change in wording changes the response.

Interpret a control before choosing a mechanism

In an invented study, investigators give one cell group a compound dissolved in a solvent. The second group receives only the solvent. If the item asks what the comparison controls for, the answer is effects of the solvent and its delivery, under otherwise comparable conditions. The comparison does not by itself identify how the compound works.

Distinguish a twofold value from a percentage increase

A treatment group shows 12 units of activity and a control group shows 6 units. Treatment activity is two times the control value. The relative increase over control is 100%. Read whether the question asks for a ratio, a difference in units or a percentage increase.

Separate the result from what it can establish

An observational study finds that participants who chose evening classes scored higher on a later quiz. Prior knowledge or other differences could influence both class choice and quiz scores. The result supports an association in this group. A causal explanation requires additional evidence or stronger design.

Match the author’s scope in CARS

An invented author argues that public archives help researchers when their records are catalogued consistently. The claim concerns a condition under which archives help. A choice saying all public archives help regardless of their catalogues removes the condition and makes the claim broader than the passage supports.

Use the new information in a beyond-the-text item

Suppose the same author says consistency matters because it reduces search time. A question describes a tool that finds records across inconsistent catalogues with equal speed. That information would weaken the particular search-time rationale. It would leave open other reasons for consistent cataloguing.

Use the Fencing Method to practise instructions

Start with a short sentence you can check. Add one precise detail, then the relationship or action the task calls for. Use the same instruction with fresh material. In a selected-response test, the sentence is a practice check for deciding which option fits.

1. The groups differ.
2. The treated group had twice the activity of the vehicle control.
3. The treated group had twice the activity of the vehicle control under the measured conditions.
4. Apply the same pattern to another figure. Name the comparison, give its size and limit the claim to what was measured.

Read the eduKate Fencing Method for Vocabulary.

Practise and check your answers

Check the result and its reference group

For each passage practice set, name the group, outcome and measured unit before reading the options. When asked for a mechanism, identify which observation the mechanism must explain. After answering, ask whether your explanation fits the control group and the direction of the effect.

Keep a separate record of CARS errors

Mark whether a missed item asked about the author’s own position, another view, a specific line or a new case. Write one sentence explaining which part of the text should guide the answer. Test the same skill on a fresh passage.

Practice 1. A stem asks for the least likely explanation. What should you check before selecting?

Identify the explanations supported by the evidence, then choose the one with the weakest fit to the stated results.

Practice 2. A graph reports concentration in micromoles per litre. The question asks for change in concentration. Which units belong with the answer?

Use the same concentration unit unless the question specifies a conversion. Change is the difference between the relevant readings.

Practice 3. A passage gives a cause as the view of a researcher and then challenges it. Whose view is it?

Attribute it to the researcher. Read the author’s challenge separately.

Practice 4. What does a vehicle control help separate?

It helps separate the effect of the active treatment from effects associated with the delivery medium.

Frequently asked questions

Should I bring scientific facts into a CARS question?

Ground the answer in the passage and any facts the question adds. AAMC says the material supplies the information needed.

Do all MCAT questions use a passage?

CARS questions are passage-based. The science and behavioural sections also include stand-alone questions.

Which practice materials should I use for the interface?

Use AAMC’s current official preparation materials and current test-day directions.

Official sources and next reading

• AAMC MCAT overview
• AAMC Critical Analysis and Reasoning Skills overview
• AAMC MCAT frequently asked questions
• AAMC 2026 MCAT Essentials
• AAMC 2027 MCAT Essentials

Related guide in this series · Advanced Placement examination instructions

Read eduKateSG’s 200-word vocabulary guide for more ways to group and practise vocabulary.

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