AP Psychology Unit 1 practice questions
Try 10 multiple-choice questions from Unit 1 here. Pick an answer to see why it's right or wrong, then take the timed test above for a full AP-style set.
Question 1
Source:Adapted from Drug and alcohol dependence. Verweij et al. (2018). Heritability of lifetime ecstasy use.
Researchers investigated the extent to which genetic factors influence lifetime ecstasy use. The sample comprised 8,500 twins and siblings aged between 18 and 45 years from 5,402 families registered at the Netherlands Twin Registry. Participants filled out a questionnaire that included a question about whether they had ever used ecstasy during their lifetime. The researchers used a classical twin design to determine what proportion of individual differences in ecstasy use could be attributed to genetic factors, shared environmental factors, and other residual factors. Twin pairs included both identical twins, who share 100% of their DNA, and fraternal twins, who share approximately 50% of their DNA like any sibling pair. The researchers then analyzed the data to estimate the heritability of lifetime ecstasy use by comparing how similar identical twins were to each other compared to how similar fraternal twins were to each other.
Factor Percentage of Individual Differences Explained Genetic factors 74% Shared environmental factors 5% Residual factors 21% Which of the following best explains why the researchers cannot establish a direct cause-and-effect relationship between genetics and ecstasy use?
The study relies on measuring naturally occurring variables without experimental manipulation.
The researchers utilized self-report questionnaires rather than direct physiological drug testing.
The sample includes both identical and fraternal twins from the same registry.
The residual factors account for a significant portion of the individual differences.
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Answer: (A)
Experimental designs require the manipulation of an independent variable and random assignment to establish cause-and-effect relationships. The described twin study measures naturally occurring genetic similarities and self-reported behaviors, making it a correlational design that can only identify predictive relationships between heredity and drug use.
Question 2
An adoption study tracked personality trait scores (extraversion) for 80 adopted children, their biological parents, and their adoptive parents. The correlation between adopted children and biological parents was r = 0.42; between adopted children and adoptive parents was r = 0.31. Based on these data, which conclusion about the heredity-environment interaction is most appropriate?
Extraversion shows moderate genetic influence, but adoptive family environment also contributes to personality expression
Extraversion is primarily determined by adoptive family environment, as shown by the correlation with adoptive parents
Genetic factors have no meaningful influence on extraversion because the correlation with biological parents is below 0.50
Adoptive parents have stronger genetic influence on extraversion than biological parents because they directly raise the children
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Answer: (A)
The higher correlation with biological parents (0.42) than adoptive parents (0.31) indicates genetic contribution to extraversion, since adopted children share genes but not environment with biological parents. However, the substantial correlation with adoptive parents (0.31) demonstrates environmental influence despite no genetic relationship.
Question 3
A study tracked temperament (activity level) in 100 identical twin pairs from infancy through age 10. At age 1, twins showed correlation r = 0.78. At age 5, correlation was r = 0.71. At age 10, correlation was r = 0.64. What does the declining correlation pattern suggest about the heredity-environment interaction across development?
Accumulated environmental experiences increasingly differentiate genetically identical individuals as they develop
Genetic influence on temperament decreases with age because environmental factors gradually replace genetic control
Identical twins become genetically more different over time, explaining why their temperament correlation declines
The declining correlation demonstrates that heredity has no meaningful influence on temperament because the correlation is not stable
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Answer: (A)
The declining identical twin correlation (0.78 → 0.71 → 0.64) indicates that despite genetic identity, twins become increasingly different over time. This pattern reflects accumulating environmental influences: different friendships, school experiences, activities, and life events gradually shape temperament expression differently in each twin.
Question 4
A family study examined risk for depression across relatives with varying genetic and environmental similarity. The data show: identical twins raised together 67%, identical twins raised apart 45%, fraternal twins raised together 38%, biological siblings raised together 32%, adoptive siblings raised together 15%. What pattern best illustrates how heredity and environment jointly influence depression risk?
Both genetic similarity and shared environment contribute to depression risk, with genetic factors showing stronger influence
Shared family environment is the primary determinant of depression risk because all family members show higher rates than adoptive siblings
Depression risk is determined entirely by genetics because identical twins show the highest concordance rates
Biological siblings raised together show higher depression risk than fraternal twins raised together because they share more genes
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Answer: (A)
Identical twins raised together (67%) exceed identical twins raised apart (45%), demonstrating shared environment adds to genetic influence. However, identical twins raised apart (45%) substantially exceed adoptive siblings raised together (15%), indicating genetic factors contribute more than shared environment alone. The pattern shows heredity and environment both matter, but genetic similarity produces larger risk differences.
Question 5
A study examined the heritability of risk-taking behavior in 150 identical twin pairs and 150 fraternal twin pairs, all recruited from college populations. Identical twins showed correlation r = 0.64; fraternal twins showed correlation r = 0.41. However, when researchers examined only participants who reported high parental monitoring during adolescence, identical twins showed r = 0.52 and fraternal twins showed r = 0.38. What does the reduced identical-fraternal difference in the high-monitoring group suggest?
Parental monitoring constrains genetic expression of risk-taking by providing environmental structure that overrides genetic predisposition
Parental monitoring eliminates genetic influence on risk-taking because the identical-fraternal difference decreases
Genetic influence on risk-taking increases with parental monitoring because identical twins show lower correlation in the monitored group
Parental monitoring has no effect on the heredity-environment interaction because fraternal twins show similar correlation in both groups
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Answer: (A)
The identical-fraternal difference decreased from 0.23 (0.64 - 0.41) in the full sample to 0.14 (0.52 - 0.38) in the high-monitoring group. This smaller genetic effect under monitoring indicates that environmental structure reduces the proportion of risk-taking variation attributable to genetic factors.
Question 6
A family study examined empathy scores across biological relatives with varying degrees of genetic similarity and environmental contact. The data show: identical twins living together 0.68, identical twins living apart 0.61, fraternal twins living together 0.44, fraternal twins living apart 0.39, biological siblings living apart 0.35, adoptive siblings living together 0.22. What does the pattern of these correlations best illustrate about the heredity-environment interaction?
Both genetic similarity and shared environment contribute to empathy, with genetic factors showing stronger influence overall
Shared environment is the primary determinant of empathy because adoptive siblings show lower correlation than all biological relatives
Genetic factors determine empathy entirely because identical twins show the highest correlations regardless of living situation
Living apart eliminates environmental influence on empathy because separated twins show substantial correlations
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Answer: (A)
Identical twins living apart (0.61) exceed fraternal twins living together (0.44), demonstrating genetic similarity outweighs shared environment. However, identical twins living together (0.68) exceed identical twins living apart (0.61), showing shared environment adds to genetic influence. The pattern shows both factors matter, but genetic similarity produces larger differences.
Question 7
A study measured neuroticism correlations for 150 identical twin pairs raised together (r = 0.52) and 150 pairs raised apart (r = 0.48). What does the small difference indicate about neuroticism?
Genetic factors substantially influence neuroticism while shared environment contributes little.
Shared environment primarily determines neuroticism because groups show similar correlations.
Neuroticism is entirely genetic because identical twins correlate similarly across rearing.
Twins raised apart show higher correlation because separation increases gene activity.
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Answer: (A)
The near equal correlations indicate strong genetic influence and minimal shared environmental effect. If shared family environment mattered, twins raised together would be much more similar than those raised apart.
Question 8
A researcher measured heart rate, pupil diameter, and digestive enzyme secretion in participants during a timed math competition. Heart rate and pupil diameter increased significantly during the task, while digestive enzyme secretion decreased. Which nervous system division is primarily responsible for this pattern of physiological changes?
The sympathetic nervous system, which mobilizes resources for the stressful task by increasing arousal and redirecting energy away from digestion
The parasympathetic nervous system, which prepares the body for sustained mental effort by increasing heart rate and pupil dilation
The somatic nervous system, which controls the voluntary muscles needed to write answers and therefore increases all physiological arousal
The central nervous system, which directly controls all organ systems and produces these changes through direct neural pathways to the heart and digestive organs
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Answer: (A)
Recognizing the coordinated pattern of increased heart rate, dilated pupils, and decreased digestion reveals sympathetic activation during stress. The data shows the classic 'fight or flight' response where the sympathetic division prioritizes immediate action over maintenance functions, demonstrating understanding that the autonomic nervous system's divisions produce opposing effects on organ systems.
Question 9
A researcher recorded heart rate, blood pressure, and salivary flow rate in participants during a public speaking task. The data show increased heart rate (from 70 to 110 bpm), increased blood pressure (from 120/80 to 145/95 mmHg), and decreased salivary flow (from 0.8 to 0.3 mL/min). Which nervous system division produces this coordinated pattern of responses?
The sympathetic nervous system, which mobilizes cardiovascular resources while suppressing digestive functions during the stress of public speaking
The parasympathetic nervous system, which increases heart rate and blood pressure to enhance cognitive performance during public speaking
The somatic nervous system, which increases heart rate through voluntary muscle contraction and decreases salivation through conscious control
The central nervous system directly controls all cardiovascular and digestive responses through motor neurons to the heart and salivary glands
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Answer: (A)
The coordinated increase in heart rate and blood pressure paired with decreased salivation reflects sympathetic activation's characteristic effects. The data pattern demonstrates the 'fight or flight' response redirecting resources toward cardiovascular function and away from digestion. Students must recognize that multiple organ systems show coordinated sympathetic effects, not isolated responses.
Question 10
Researchers measured how long it took participants to recover from a stress task, defined as returning to baseline heart rate. Participants with intact nervous systems recovered in 5 minutes, participants with partial autonomic nervous system damage recovered in 12 minutes, and participants with complete autonomic nervous system damage showed no recovery. What does this pattern indicate about the parasympathetic nervous system's function?
The parasympathetic nervous system actively restores the body to baseline by decreasing heart rate and promoting recovery after stress
The parasympathetic nervous system allows the body to return to baseline by passively ceasing to stimulate heart rate after stress ends
The sympathetic nervous system actively restores the body to baseline by decreasing heart rate and promoting recovery after stress
The parasympathetic nervous system actively maintains baseline during stress by decreasing heart rate and preventing stress responses
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Answer: (A)
The intact group's rapid recovery reflects parasympathetic activation that counteracts sympathetic stress responses. Partial autonomic damage slows recovery, and complete damage prevents recovery, demonstrating the parasympathetic division's essential role in the 'rest and digest' function. Students must infer from the recovery time data that the parasympathetic system actively restores homeostasis rather than simply being absent during stress.
What's on the AP Psychology Unit 1 practice test
The standard version takes about 94 minutes and follows the timing and directions of the AP exam, sized to one unit:
- 20 Multiple Choice Questions (24 minutes)
- 1 FRQ – FRQ 1 – Article Analysis Question (AAQ) (35 minutes)
- 1 FRQ – FRQ 2 – Evidence Based Question (EBQ) (35 minutes)
Questions are drawn from 1063 multiple-choice questions and 28 FRQs written for Unit 1, Biological Bases of Behavior.
Practice AP Psychology Unit 1 FRQs
Answer the unit's free-response questions one at a time and get a score on every part.
- FRQ 1 – Article Analysis Question (AAQ) (13 questions)
- FRQ 2 – Evidence Based Question (EBQ) (15 questions)
Review Unit 1 before you start
- 1.1 Interaction of Heredity and Environment
- 1.2 Overview of the Nervous System
- 1.3 The Neuron and Neural Firing
- 1.4 The Brain
- 1.5 Sleep
- 1.6 Sensation