Biology Multiple Choice Questions

Overview of the Multiple Choice Section

Section I of the AP Biology Exam consists of 60 multiple choice questions, accounting for 50% of the exam score. You will have 90 minutes to complete these questions, and you may use a four-function, scientific, or graphing calculator on both sections of the exam.

The multiple choice questions are presented as individual questions or as sets of four to five questions. All six AP Biology science practices are assessed, with each having a specific exam weighting. This section will test your ability to:

• Explain biological concepts, processes, and models
• Analyze diagrams, flowcharts, and other visual representations
• Apply the scientific method
• Perform mathematical calculations to analyze data
• Support scientific claims with evidence

Tips for the Multiple Choice Section

1. Be Precise and Neat

   • On the AP Exam, you will fill in your multiple choice answers on a scantron sheet. Incorrectly filled bubbles or improperly erased pencil marks can cause the machine to misgrade your answer. Ensure that you completely fill in the bubbles and erase completely if you decide to change an answer.

2. Pace Yourself

   • Although you have about a minute per question, it’s a good idea to aim for under a minute per question on your first pass. This way, you’ll have extra time at the end to revisit tricky questions that you may have skipped or guessed on.

3. Answer Every Question

   • There is no guessing penalty on the AP Biology Exam. Make sure to answer every question, even if you are unsure of the answer. A well-educated guess is better than leaving it blank.

4. Use Multiple Choice Strategies

   • Apply test-taking strategies such as the process of elimination, educated guessing, and effective time management. It’s crucial to enter the exam with a specific strategy, such as skipping the hardest questions initially and returning to them later. By eliminating two of the four options, you have a 50% chance of getting the question correct.

5. Read Carefully and Stay Focused

   • It’s easy to lose focus during a long test. Pay close attention, especially to words like “EXCEPT” or “NOT,” which can change the meaning of the question. If you skip a question, make sure to skip the corresponding bubble on the scantron sheet to avoid misalignment errors.

6. Read Questions First for Data Analysis

   • For questions that include data, paragraphs, charts, or graphs, read the questions first to understand what information is needed. Often, only part of the data or description is relevant to the answer. This technique can save time and prevent overanalyzing unnecessary details.

7. Familiarize Yourself with Question Styles

   • The multiple choice section often contains questions in sets that are based on a paragraph, experiment, chart, or graph. Familiarize yourself with how these questions are presented, as understanding their format will make you more comfortable during the exam.

Sample Questions and Explanations

Question 1:
The lac operon is found in prokaryotes and contains structural genes, a promoter, and an operator. Why do we study the lac operon?
A. It is the main way gene transcription is regulated.
B. It shows the difference between prokaryotes and eukaryotes.
C. It helps us understand how to control the cell cycle during uncontrollable growth.
D. It shows how RNA is processed after it is transcribed.

Answer: A
Explanation: This question requires understanding why the lac operon is important, not just what it is. Choice A is correct because the lac operon serves as a classic example of gene regulation through the coordination of transcriptional control. Choice B can be eliminated because although operons are unique to prokaryotes, their presence is not how we distinguish prokaryotes from eukaryotes. Choice C is incorrect because operons do not control cell cycle regulation. Choice D is incorrect because operons regulate transcription, while choice D addresses post-transcriptional processing, which is not relevant here.

Question 2:
Peter and Rosemary Grant spent 30 years observing finches on the Galapagos Islands. In 1977, a severe drought caused a shortage of small, soft seeds, leaving primarily large, tough seeds that finches do not typically eat. A year later, it was found that the average width of finches’ beaks had increased.
Which statement best explains the increase in beak size?
A. The finches with smaller beaks adapted and made their beaks bigger.
B. The finches with bigger beaks killed the finches with smaller beaks.
C. Finches with larger beaks were able to eat tough seeds and were healthier, leading to increased reproduction.
D. All finches increased their beak size to be able to eat the tougher seeds.

Answer: C
Explanation: This question addresses natural selection. Choice C correctly reflects Darwin’s theory of natural selection—individuals with advantageous traits (i.e., larger beaks) had greater success in surviving and reproducing during the drought, leading to more offspring with larger beaks. Choice A is incorrect because individual finches cannot willfully change their beak size. Choice B is incorrect because there is no evidence of aggression between finches related to beak size. Choice D is incorrect for the same reason as A, as it suggests a Lamarkian idea of evolution through self-directed change.

Question 3:
Which of the following explains how beak size increased in the finch population?
A. A new allele appeared due to mutation.
B. A new trait appeared due to the bottleneck effect.
C. A new trait appeared due to recombination of alleles.
D. A change in gene frequency was due to selective pressure from the environment.

Answer: D
Explanation: The correct answer is D, as it addresses natural selection due to selective pressure from the environment—the availability of tough seeds during the drought. Choices A, B, and C do not specifically address how selective pressure acted on existing genetic variation, leading to an increase in beak size frequency.

Additional Tips for Success

• Practice Regularly: Work through multiple choice practice questions to build confidence and familiarity with the question styles.
• Understand Core Concepts: Focus on understanding key relationships in biology, like feedback mechanisms, homeostasis, and energy flow, rather than rote memorization.
• Know Experimental Setups: The AP Biology exam often includes experimental data interpretation. Understanding how variables, controls, and hypotheses are used will help tackle data-based questions.