#Question id: 1239
#Unit 4. Cell Communication and Cell Signaling
GTPases serve in many signal transduction pathways and the presence of GTP or GDP dictates whether the pathway is on or off, respectively. Which of the following statements is TRUE regarding guanine nucleotide exchange factors (GEF) and the role in these signaling pathways?
#Question id: 4991
#Unit 11. Evolution and Behavior
Which of these fly organs, as they exist in current fly populations, best fits the description of an exaptation?
#Question id: 5234
#Unit 11. Evolution and Behavior
Which of the following would, if it had acted upon a gene, prevent this gene from acting as a reliable molecular clock?
#Question id: 24230
#Unit 4. Cell Communication and Cell Signaling
#Question id: 23310
#General Aptitude