If you're taking AP Biology, it's a good idea to familiarize yourself with the exam before you get too far into the course. Preparing ahead of time for the format of the exam and fully understanding which concepts are covered can go a long way towards earning a high score (and potentially getting college credit).
This article will take you through the structure and scoring of the exam, plus give you some tips on the best ways to study for AP Biology!
How Is the AP Biology Exam Structured?
The AP Biology test has a multiple-choice section (that also includes grid-in questions, so it’s not purely multiple choice) and a free-response section.
The Multiple-Choice Section Is:
- 63 multiple-choice questions
- Six grid-in questions
- 90 minutes long
- Worth 50 percent of your score
Grid-in questions ask you to integrate mathematical and scientific skills to make calculations and then enter your answer into a grid on the answer sheet (essentially, these are short-response questions similar to grid-in questions on the math SAT).
The Free-Response Section Is:
- Six short-response questions
- Two long-response questions
- 90 minutes long (including a 10 minute reading period)
- Worth 50 percent of your score (25 percent for the short responses and 25 percent for the long responses)
Questions on Both Parts of the Exam Will Ask You To:
- Understand how graphical and mathematical models can be used to explain biological principles and concepts
- Make predictions and justify events based on biological principles
- Implement your knowledge of proper experimental design
- Interpret data
The AP Biology exam is 3 hours in total. In 2018, the test will take place on Monday, May 14th at 8 AM.
Is this coffee smiling at me? Or am I delirious from lack of sleep?
Content Background and Sample AP Biology Questions
The AP Biology test doesn't include a set number of questions dealing with each topic area, but you should note that the exam is centered around four major themes (or "Big Ideas" as the College Board prefers to call them) that run throughout the course. Here's a list of these four themes followed by the topics that fall beneath each of them:
Big Idea #1: The Process of Evolution Drives the Diversity and Unity of Life.
Topics that fall into this category include:
- Natural selection
- Mathematical modeling of populations
- Species classification
Big Idea #2: Biological Systems Utilize Free Energy and Molecular Building Blocks to Grow, to Reproduce and to Maintain Dynamic Homeostasis.
Topics that fall into this category include:
- Molecular biology
- Cell structure
- Cellular respiration
- Thermodynamics and homeostasis
- The immune response
Big Idea #3: Living systems store, retrieve, transmit and respond to information essential to life processes.
Topics that fall into this category include:
- The cell cycle (mitosis and meiosis)
- Communication between cells
- The endocrine system
- The nervous system
Big Idea #4: Biological systems interact, and these systems and their interactions possess complex properties.
Topics that fall into this category include:
- Plant structure
- The circulatory system
- The musculoskeletal system
Now that you have a basic content outline, here are some examples of the types of questions you'll see on the test so that you can get an even better idea of what to expect.
Here is an example of a multiple-choice AP Biology exam question:
This question sounds kind of complicated, but let’s break it down. The first sentence is background information that isn’t really necessary to answer the question besides the fact that it tells us we’re talking about sickle cell anemia. This is helpful if you remember basic facts about the disease that you can use to contextualize the question.
The main part of the question asks what will be affected when you replace a hydrophilic amino acid with a hydrophobic one on a hemoglobin protein. Based on your knowledge of sickle cell anemia and molecular properties, you should be able to eliminate choices B and C, which don’t have much to do with the abnormality described in the question. Choice D can also be eliminated because the internal secondary structure of the protein is not altered by the existence of the hydrophobic group. This would only affect how the molecule interacts externally with other hemoglobin molecules, as in choice A (the correct answer).
Here’s an example of a grid-in question that you might see on the AP Biology test:
This question just asks you to read a graph and perform some basic calculations. We can see from the graph that from day 3 to day 5, the population size grew from 200 to 900 individuals. This means it increased by 700 individuals in total. If we divide 700 by the time period of two days, that's a mean growth rate of 350 individuals per day. You would enter “350” into the grid for this question!
Bacteria gettin' it on
Short Free Response
Here’s an example of a short free-response question you might see on the test:
On this particular question, you could earn a maximum of four points (one for each type of data you describe in part a and one for the explanation for each in part b). Types of data and corresponding explanations you could cite for points include:
Data Description: The ability of the plants to produce viable seeds/offspring in nature.
Explanation: This is consistent with the definition of a biological species.
Data Description: Comparison of the two plants’ DNA sequences or structures of other conserved molecules.
Explanation: Sufficient similarity between the DNA structures would support the existence of a single species.
Data Description: Discovering the existence of fertile hybrid plant populations living between the two other populations of plants.
Explanation: This is also consistent with the definition of a biological species (again, ability to produce fertile offspring).
There must be jobs out there where you just have to collect plant samples. Start building your experience now by never showering.
Long Free Response
Here’s an example of a long free-response question you might see on the test:
On this question, you could earn up to ten points total.
Part A was worth 3 points. To earn these points, you had to:
- Create a graph that was correctly labeled, scaled, and used proper units.
- Make it a bar graph with correctly plotted sample means.
- Show the standard error (+/- 2) on your graph above and below the means.
- Identify populations I and III as the most likely to have statistically significant differences in the mean densities.
- Explain why this was the case (because the margins of error do not overlap for the mean densities of these two populations; 9+2 is less than 14-2).
- You would earn two points for identifying the independent variable (presence of herbivores) and dependent variable (trichome density).
- You would earn one point for identifying a control treatment (absence of herbivores).
- You would earn one point for identifying an appropriate duration of the experiment (more than one generation of plants).
- The final point would be earned by predicting experimental results that would support the hypothesis (higher trichome density under the experimental conditions as compared to the control conditions).
Ugh gross! This leaf is full of trichomes.
How Is the AP Biology Exam Scored?
As I mentioned, the multiple-choice section (including the grid-ins) makes up 50 percent of your score, and the free-response section makes up the other 50 percent. For the multiple-choice section, it’s easy to calculate your raw score. You get one point for each question you answer correctly. There are no point deductions for incorrect answers or answers that you leave blank. This is also true for the grid-in questions.
For the free-response section, which is scored by AP graders rather than by computer, it’s a bit more complicated. You’ll answer six short response questions that have different point values depending on their complexity. Three of the short response questions are scored out of three points. The other three are scored out of four points. Each long free-response question is scored on a ten-point rubric.To figure out your final score, you’ll need to do a couple more calculations. This can change from year to year based on the performance of students, but this is the most recent estimate I have of the methodology:
- Multiply the number of points you got on the multiple-choice section by 1.03
- Multiply the number of points you got on the two long free-response questions by 1.5
- Multiply the number of points you got on the short free-response questions by 1.43
- Add all of these numbers together to get your raw score
Here is a conversion chart so you can see how raw score ranges translate into final AP scores. I've also included the percentage of students who earned each score in 2016 to give you an idea of what the score distribution looks like:
Percentage of Students Earning Each Score (2016)
For example, if you earned 40 points on the multiple-choice section, 13 points on the long response questions, and 14 points on the short response questions, your score would be (40*1.03) + (13*1.5) + (14*1.43) = 80.72. This indicates that you would earn a 4 on the real AP Biology test.
If you want to spice things up a little bit, you can even do the math on a snazzy calculator with red buttons! Isn't this fun?!?!?
What’s the Best Way to Prep for the AP Biology Exam?
Now that you know all about what's on the AP Biology test, it's time to learn how to ace it. Follow these four tips to end up with a great score.
Tip #1: Review Your Labs
Labs make up about 25 percent of the AP Biology course, and for good reason. It’s important to understand how labs are conducted and how the principles behind them relate to the main ideas of the course. This will help in answering both free-response and multiple-choice questions that deal with lab scenarios on the test.
Many free-response questions ask you to identify the components of a proposed experiment (dependent and independent variables) or design a lab to test a certain hypothesis. You might have forgotten about the labs you did towards the beginning of the year, so take extra care to go over them. Make sure you understand exactly how they were conducted and what the results mean.
Tip #2: Learn to Connect Small-Scale Terms with Large-Scale Themes
The AP Biology test covers four major themes:
- Energy use in biological systems
- Processing of stimuli in biological systems
- Interaction of biological systems
Under each of these umbrella topics, there are many terms and ideas that you'll need to review. Memorization can be a big part of studying for AP Biology. However, memorizing the definitions of terms will only get you so far. You'll also need to understand how they relate to each other and to the four themes listed above.
The exam emphasizes making connections between biological terms, corresponding biological systems, inputs and outputs of these systems, and the overall impact on living organisms and the environment. You should be able to follow a chain of reasoning from the specific to the broad, and vice versa.
If this tree is AP Biology, the four big branches are the four themes, and all the smaller offshoots are different terms and concepts. For it to survive, there has to be a lot of communication between the trunk and the rest of the tree!
Tip #3: Practice Eliminating Irrelevant Information
Both multiple-choice and free-response AP Biology questions include lots of scientific terminology and visual aids. This test format might be intimidating if you’re not used to it. It’s important to practice sorting through this jumble of information so that you can quickly get to the root of the question rather than obsessing over small details you don’t understand. Try underlining important words and phrases in the question to stay focused on the main points and avoid misleading distractions.
You should also practice responding to free-response questions in a straightforward way without any unnecessary fluff. Remember, this isn’t an English test; the graders are just looking for clear facts and analysis. Make it easy for them to give you points!
Tip #4: Learn Good Time Management
The AP Bio exam is pretty long (even for an AP test), and many of the questions require quite a bit of thought. You need to make sure that you have a good handle on time management before exam day. The best way to do this is to take multiple practice tests.
There are 69 questions total in the multiple-choice section, and you have 90 minutes to answer them. This comes out to about one minute and 15 seconds for each question. Based on that fact, you should spend no more than a minute on each multiple-choice question the first time you go through the test. If you find yourself spending extra time on a question, skip it and come back to it later. It’s best to give yourself some leeway in case you run into trouble on the grid-in questions.
You also have 90 minutes for the free-response section, but you'll spend different amounts of time on the long and short questions. Limit your time on the long questions to 22 minutes each or less (44 minutes total) and your time on the short questions to 6 minutes each or less. If you can’t work this fast right away, you should do additional practice free-response questions until you feel comfortable with the time constraints.
Really get to know the test. Take it on a romantic getaway, and watch the sunset with it. Deep down, the AP Biology exam just wants to be understood.
The AP Biology exam is three hours long, with two sections that take up an hour and a half each. The multiple-choice (and grid-in) section has 69 questions total, and the free-response section has eight questions total.
The content of the exam spans four major themes or "Big Ideas" that are central to the course. These include evolution, energy use within biological systems, the processing of stimuli within biological systems, and interactions that occur between biological systems on a larger scale in nature.
Questions ask you to connect specific terms and concepts to these central topics. They will test your ability to interpret data, make predictions and inferences based on biological evidence, and analyze different experimental scenarios. It's a tough test, but if you study hard and know what to expect, you're perfectly capable of a great score!
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Samantha is a blog content writer for PrepScholar. Her goal is to help students adopt a less stressful view of standardized testing and other academic challenges through her articles. Samantha is also passionate about art and graduated with honors from Dartmouth College as a Studio Art major in 2014. In high school, she earned a 2400 on the SAT, 5's on all seven of her AP tests, and was named a National Merit Scholar.