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How to Do Well on the AP Biology Free Response (FRQ) - Examples with Step by Step Breakdown

This year's AP exams are all free response and no multiple choice, including the AP Biology exam. Of course, this means that students taking the AP Biology exam should focus on doing free response practice questions and understanding how they are scored.

What is the structure of a FRQ?

There are multiple parts to a FRQ (part a, part b, etc.) but they typically revolve around the same topic. Usually, there is also a diagram, graph, or table provided in the question. Students must refer to it and apply analytical skills in order to answer the question. Even though the visual may be presented first, I highly recommend skimming through the text first. The text usually provides an explanation of what is shown in the visual.

Here are some past FRQ from real AP Biology exams from College Board:

2018 FRQ #2:

This question is more difficult and time-consuming than usual because there are two visuals to analyze. Then, the student must understand how they tie together. There are also five parts to the question, more than the average. See below for a step-by-step guide to answering this problem.

Also notice that key parts of the question are bolded. This helps students check their work and make sure they have answered everything.

2014 FRQ #2:

This question from 2014 provides a table but it is only needed to answer part (a), which is about evolutionary relationships. Parts (b) and (c) test the student on a different topic (immune responses) and they draw on the students' own knowledge of how the immune system works.

2016 FRQ #4:

This question from 2016 is the most straightforward of the three examples here. There are only two parts to the question and the diagram is simple. Both parts of the question are about protein synthesis.

You can find more past FRQ on the College Board AP Central site.

What does a full-score AP Biology FRQ answer look like?

For FRQ, including the right "buzzwords" is very important for getting a good score. The graders have a set of keywords they look for in the answer. If the answer contains more than a certain number of keywords, then it will get a full score. Of course, these words must be used in the right context and be correctly defined when needed.

As demonstrated in 2018 FRQ #2, the student also needs to connect different concepts together and explain them in a concise manner when answering questions.

Step by Step Problem Solving - 2018 FRQ #2

In addition to studying and reviewing the material, the best way to prepare for the AP is to do plenty of practice problems. Let's walk through one now, step by step. PART (A):

STEP 1: Read the background and other information provided

Read through the text. Get a sense of what biology topic the problem is testing you on. Here, the topic seems to be cell communication and signaling pathways.

STEP 2: Skim the diagrams

Skim the diagram and table and understand generally what they are showing. The diagram shows the enzyme pathway that ultimately triggers an immune response. The table shows different fractions of cells and the various enzymes found in each fraction. It is important to understand here that the fractions are an estimate for various locations inside the cell, such as the cytoplasm or nucleus. This can be inferred from the description of the table.

STEP 3: Read the question and understand where to look for the answer

Read the question carefully. Part (a) refers directly to step 3 in the diagram, so let's go there. It asks about the relationship between step 3 and the formation of pores and release of interleukin from the cell. In this case, the text describing the diagram helps much more than the diagram itself so let's focus on the text. It says, "When caspase-1 cleaves gasdermin (step 3), the N-terminal portions of several gasdermin proteins associate in the cell membrane to form large, nonspecific pores."

Note that part (a) is a "hunting" type of question -- it requires you to look for the answer using background information and visuals already provided. Other types of questions may require you to draw completely from your own knowledge.

STEP 4: Analyze and answer

Use the text to understand what happens if step 3 does not happen. A good answer to part (a) would be:

If step 3 is inhibited, gasdermin won't be cleaved. Then there won't be N-terminal portions of gasdermin present to form the large pores. However, that activity of gasdermin does not impact the release of interleukin, since caspase-1 is still present to help release interleukin. Thus, interleukin release is unaffected.


The first part of this question requires you to recall your knowledge about enzyme structure and activity. A good answer is:

Because enzymes are proteins, cleaving caspase-1 will alter the shape of the enzyme and activate it.

The second part requires you to refer to the diagram again and use analytical skills to understand the effects of increasing inactive caspase-1. A good response is:

From step 1, we can infer that if there is more inactive caspase-1 to start with, there will be more available to convert to active caspase-1 once bacterial infection occurs. The increase in active caspase-1 also increases the immune responses downstream, such as the release of interleukin and formation of pores.


This question refers to the table of cellular proteins and fractions. As mentioned earlier, you should recognize that the cell fractions are just for flagging different locations within the cell. Take the first row, for example. The only protein present in Fraction 1 is aconitase, which is involved in Kreb's cycle. This tells us that Fraction 1 contains mitochondria.

Let's apply the same logic to determine where the NF-kB protein is located. The table shows us that NF-kB is in Fractions 2 and 3. What else is in those fractions? That is the key. DNA polymerase is in Fraction 2 and a glycolytic protein (involved in glycolysis) is in Fraction 3. Recall that glycolysis occurs in the cytoplasm, so we know that NF-kB is found in the cytoplasm since it's found in the same fraction as the glycolytic protein.

The second part of this question asks where N-terminal gasdermin would be found. The diagram showed us that it would occur in the cytoplasm near the cell membrane. Now we just need to determine which fraction corresponds to which location in the cell. To do this, identify which other proteins are found in each fraction. Fraction 3 contains the glycolytic protein so it represents the cytoplasm. Fraction 4 contains sodium-potassium pumps -- recall that these are found in the cell membrane. Thus, N-terminal gasdermin is found in both Fractions 3 and 4. *Note that the question just asks us to "identify", not explain, so don't spend extra time to write a justification/explanation for why it's Fractions 3 and 4.


This question is easier because we don't need to refer to any visuals. It's just information recall. A good answer would be:

In a hypotonic environment, water would enter the cell because the concentration of solutes inside the cell is greater than concentration outside the cell.


This is another information recall question. It might seem like we need to refer to the diagram again, but we just need to recall what interleukins do and what the result of pore formation would be in the event of an immune response. A good answer is:

Released interleukins will recruit more immune cells to the infected area to fight the pathogens. Pore formation will ultimately cause the infected cell to lyse, thus killing it.

Now that we have walked through a FRQ, apply the same logic and steps to other sample FRQs and do plenty of practice! Test corrections are also crucial because you learn what types of responses, the level of detail, the buzzwords, etc. that the graders are looking for.



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