Passage I
Figure 1 depicts some of the steps of protein synthesis in eukaryotes.
In yeast, the genes that are expressed at a given time depend on environmental conditions, such as the glucose concentration in the environment.
Saccharomyces cerevisiae, a type of yeast, was grown for 12 hours on a growth medium containing glucose. The transcription rates of 4 genes (Genes 1—4) were determined. The relative transcription rate (RTR) of each gene was then calculated using the following formula:
The results appear in Figure 2.
Figure 3 shows the glucose concentration of the medium during the experiment.
Figures 2 and 3 adapted from Joseph L. DeRisi, Vishwanath Riyer, and Patrick O. Brown,“Exploring the Metabolic and Genetic Control of Gene Expression on a Genomic Scale." ©1997 by the American Association for the Advancement of Science.
4. Based on Figure 1, which of the following best describes what happens to introns during gene
expression?
Your Answer is
Correct Answer is H
Explanation
Looking at figure 1, it is found that the intron is still there when the step 1 transcription is performed, but the intron is gone when the step 3 translation is reached, so the intron has experienced the transcription but not the translation