The AP Biology exam covers a large amount of information, but fortunately, you don’t have to memorize every formula you will need for the exam. During the exam, you will be provided with a two-sided Equations and Formulas sheet to use on the test. The AP bio formula sheet will be at the front of both the multiple-choice and free-response portions of the AP Biology test.

## What's on the AP Bio Formula Sheet?

The information on the formula sheet is organized into topics. Alongside the equations, most variables and some vocabulary words are also defined; the variables are typically defined to the right of their corresponding equations.

The first page contains the following general topics that could be applied in a wide variety of ways:

• Statistical Analysis and Probability
• This includes general equations that can be used in a wide variety of experimental design questions.
• Metricx Prefixes
• This section outlines the multiplication factors, prefixes, and symbols for a wide range of the metric scale. Since such a wide range of numbers is covered, these prefixes could be used in almost any topic. When measuring the diameter cells, look for “nanometers,” but when counting cells, they may be in the mega- range!
• Definitions of Mode, Median, Mean, and Range
• Equations for Standard Deviation and Standard Error
• It is not necessary to CALCULATE the standard deviation for a set of data, but be familiar with the basic process of the calculation to better understand what standard deviation means.
• Equation for the Chi-Squared Test and Chi-Squared Table
• The equation is used with a set of data to determine whether two variables are related to each other and whether actual data aligns with expected data.
• The table is used to decide whether to accept or reject a null hypothesis depending on the degrees of freedom (number of independent variables in the data) and the critical value (determines what makes results significant).
• Laws of Probability
• These equations may be useful on the test in a few contexts but are more likely to be useful for genetics questions, especially Punnett squares!
• Hardy-Weinberg Equilibrium
• These equations are likely to show up in genetics and natural selection questions!

The second page contains a few more specialized topics:

• Rate and Growth
• Simpson’s Diversity Index
• Water Potential & Solute Potential of a Solution
• pH equation
• Surface Area and Volume

The Rate and Growth section contains a few equations related to ecology topics and how populations grow over time under certain models.

The Simpson’s Diversity Index quantifies the amount of diversity present based on the number of species and how abundant each species is.

The Water Potential & Solute Potential of a Solution section includes two equations related to active and passive transport and will most likely show up on cell structure & function questions.

The pH equation is also included underneath this category, but just as with standard deviation, you are not expected to actually perform calculations with this equation. The equation is provided as a reference to remind you what pH represents.

The Surface Area and Volume section includes many equations related to the size of a cell. You will likely only use a couple of the equations from this section of the formula sheet on your test. However, since you don’t know which will come up, you should be familiar with all of them. These equations are often used to analyze why cells are small and the factors that limit cell size.

All of the information on the formula sheet is very useful, but there is a lot. You don’t want to waste time during your preparation memorizing the information, but you definitely don’t want to spend excessive time searching for equations during the actual test. Make sure you use the sheet as you study and practice. The more you use it, the quicker it will be to find the information you need to answer relevant questions—and you might find you naturally start to remember some of the information on it!

If there are any equations or variables on the AP Bio Formula sheet that you aren’t familiar with, especially as the test date inches closer, review those topics in advance to make sure you’re ready to use the formulas if needed!