Question

Thale cress (Arabidopsis thaliana) is a small, quickly reproducing, edible plant. It has a gene locus with an allele that results in a tolerance to heavy metals, which can leech into the soil as a result of mining operations.
A genetics professor has been using a population of thale cress for a Spring semester class to practice genetic analysis skills. The professor continues using the population after a mine in started near the collection location. The professor tracks their data from year to year. The graph displays the data for the allele frequencies for a heavy metal tolerance gene. Based on the evidence, during what year was the mine built?

• A. 2002
• B. 2003
• C. 2005
• D. 2006

Answer 1

Answer: (B)

2003

Around the year 2003 the number of plants with low tolerance keeps on decreasing while that with the allele with high resistance increases in number.

So, the correct answer is '2003'