Free Response Questions (FRQ)
3 min read•january 1, 2021
This question is from the 2019 AP Biology Exam. Be sure to include specific vocabulary and try not to write more than four sentences.
You received 1/2 points for your response to part A. While the K+/H+ transport protein is responsible for the increase in pH, you needed to specifically say that the pH increases because the transport protein pumps H+ ions OUT of the vacuole. The proton pump is what is responsible for bringing the H+ ions back in. You received 1/1 points for your response to part B. You did an awesome job of explaining the hypertonic environment created.
You received 2/2 points for your answer to part a by successfully naming the transport protein AND how it leads to a decrease in pH by removing protons from the vacuole.
You received 1/1 points for your answer to part b by successfully describing the change in water potential due to the transport protein.
You received 2/2 points for your answer to part A by successfully naming the protein AND how it facilitates the change in pH.
You received 1/1 points for your answer to part B by explaining that the movement of potassium leads to a hypertonic environment.