The activators bind—and the enhanceosome forms—in a highly cooperative manner, ensuring that all three activators must be present. The following are three ways the regulators might be binding cooperatively:

I- Through direct protein–protein interactions between them

II- By changes in the DNA caused by binding of one protein helping binding of another;

III- By the fact that the activators all interact simultaneously with the coactivator.

#Question id: 8287

#Unit 9. Diversity of Life Forms

The following phylogeny shows six living species (a-f) and five ancestral (now extinct) species (#1-5). If the phylogeny had been developed on the basis of similarities in bone structure, which of the following predictions would you make in terms of the structure of a particular enzyme?

#Question id: 8288

#Unit 9. Diversity of Life Forms

Some beetles and flies have antler-like structures on their heads, much like male deer. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of ________.

#Question id: 8289

#Unit 9. Diversity of Life Forms

The term convergent evolution is most applicable to which of the following features?

#Question id: 8290

#Unit 9. Diversity of Life Forms

If, someday, an archaean cell is discovered whose rRNA sequence is more similar to that of humans than the sequence of mouse rRNA is to that of humans, the best explanation for this apparent discrepancy would be ________.

#Question id: 8291

#Unit 9. Diversity of Life Forms

Which of the following pairs are the best examples of homologous structures?

#Question id: 8292

#Unit 9. Diversity of Life Forms

Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser panda in the raccoon family (Procyonidae). If the molecular data best reflect the evolutionary history of these two groups, then the morphological similarities of these two species is most likely due to ________.