BIO 4301 Exam 2 Study Notes

Course: BIO 4301 Evolution
Exam: Exam 2
Semester: Spring 2026
Instructions:
- Students have the full class time to complete the exam.
- Only a #2 pencil and a non-cellphone calculator are allowed.
- Any detected academic dishonesty will result in a report to the Dean of Students office and a score of zero on the exam.
- Students must write their name on both the exam and the scantron.
- Students must bubble in their student number on the scantron.
- The exam consists of 40 multiple choice questions, each worth 2 points, totaling 80 points towards the final grade.
- Students must read the questions carefully, select the correct answer, and bubble the correct answer for each question on the scantron.
- Upon completion, both the scantron and the exam must be submitted.
- Good Luck!

Scenario: A population of alpacas has a gene with four alleles (A1, A2, A3, A4), each at a frequency of 0.25.
Question: What is the probability that alpaca allele A2 goes extinct due to genetic drift?
- Options:
- a. 0
- b. 0.25
- c. 0.5
- d. 0.75
- e. Impossible to determine as genetic drift is random

Follow-up on Scenario from Question 1:
Question: What is the probability that alpaca allele A2 becomes fixed via genetic drift?
- Options:
- a. 0
- b. 0.25
- c. 0.5
- d. 0.75
- e. Impossible to determine as genetic drift is random

Assumption: Alpaca allele A2 does become fixed due to genetic drift.
Question: Which of the following is said regarding genetic drift at the moment this occurs?
Considerations to Note:
- Alpaca allele A2 is in linkage disequilibrium with all other loci in the population.
- There are no heterozygotes with respect to this gene.