Question 1
In a model of a signaling pathway, kinases activate relay proteins by adding phosphate groups, and phosphatases remove them. A drug inhibits the phosphatases. What is the most likely effect after the signal is removed?
How much does the AP Biology exam cost?
For the May 2027 exams the fee is US$99 at schools in the US, US territories, Canada and DoWEA schools, and US$129 at schools everywhere else.
| US, territories, Canada | US$99 per exam |
|---|---|
| Elsewhere | US$129 per exam |
| Fee reduction | US$37 per exam for eligible students |
| On-time ordering | By November 13, 2026 |
Deadlines and extra fees
- Exams ordered from November 14, 2026, through March 12, 2027, carry a US$40 late order fee on top of the exam fee.
- An exam canceled after November 13 and by March 12, or left unused, carries a US$40 fee instead of the exam fee.
- Your school orders exams and may set its own earlier deadline and its own price; ask your AP coordinator.
Fee reductions
College Board takes US$37 off each exam for students who qualify for a fee reduction, and many states and schools add their own help. Ask your AP coordinator what applies to you.
Try 2 questions
Question 2
A purified protein is unfolded completely in a solution that breaks its hydrogen bonds and other weak interactions. When the solution is slowly removed, the protein folds back into its original shape and regains full activity, with no other molecules present. Which claim does this result best support?
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Questions people ask
How much is the AP Biology exam in 2027?
US$99 at schools in the US, US territories, Canada and DoWEA schools, and US$129 elsewhere, for exams ordered on time.
Is there a fee waiver for AP exams?
College Board gives a US$37 fee reduction per exam to eligible students, and schools and states may reduce the cost further.
What is the deadline to sign up for the AP Biology exam?
Schools order exams by November 13, 2026 without a late fee. Your school may set an earlier date.