Design an experiment using a respirometer to measure oxygen consumption in Wwxxyyzz under aerobic conditions with glucose. Include a control and one experimental variable you would test. (3 points)
| Condition | Growth rate | |--------------------|-------------| | Aerobic, glucose | 1.2 | | Anaerobic, glucose | 0.4 | | Aerobic, no glucose| 0.1 |
AP Biology 2020 – Practice Exam Organism code: Wwxxyyzz Question 1 (25 min) [Insert your data table or figure here] (a) [Your question] (b) [Your question] (c) [Your question] (d) [Your question] Wwxxyyzz Ap Bio 2020
Answer Key (for teacher use) 1(a) … 1(b) … (etc.)
Describe one mechanism that could have introduced the ‘a’ allele into the population. (1 point) Design an experiment using a respirometer to measure
Question 2 (20 min) [Insert your model or scenario here] (a) [Your question] (b) [Your question] (c) [Your question] (d) [Your question]
The ‘a’ allele encodes a transporter with a higher affinity for glucose under low‑glucose conditions. Explain how natural selection could have changed allele frequencies in this direction. (2 points) (1 point) Question 2 (20 min) [Insert your
Predict how the addition of an uncoupler of oxidative phosphorylation would affect ATP production and oxygen consumption. Explain your reasoning. (2 points)
The organism is exposed to an antibiotic that blocks the electron transport chain. Predict the relative growth rate under aerobic conditions (compared to the table) and explain how the cell would compensate. (2 points) Question 2 (20 min) A population of Wwxxyyzz is grown in a chemostat for 200 generations. Initially, all individuals have the same allele for a membrane transport protein. After 200 generations, two alleles (A and a) are present at frequencies: A = 0.3, a = 0.7.
If you meant “Wwxxyyzz” as a specific code for a real released exam, please provide more context—I can then direct you to the official College Board resources where that exam might be found (e.g., AP Classroom or past secure exams).
If the population is moved to a high‑glucose environment, predict what will happen to the frequency of the ‘a’ allele over 50 generations. Justify your prediction. (2 points)