we examine how the deregulation of growth-promoting and growth-inhibiting signaling pathways contributes to tumorigenesis. Mutations-

A. A mutation that alters a single amino acid (valine to glutamine) in the transmembrane region of the HER2 receptor

B. A deletion that causes loss of the extracellular ligand-binding domain in the EGF receptor Results-

i. dimerization of the receptor, even in the absence of the normal EGF-related ligand, transforming it into the oncoprotein, a constitutively active kinase

ii. to constitutive activation of the kinase activity of the resulting oncoprotein

iii. no dimerization, even in the presence of the normal EGF-related ligand, repression of kinase activity

which of the following results are displayed after these mutations?

#Question id: 9621

#Unit 9. Diversity of Life Forms

If this evolutionary tree is an accurate depiction of relatedness, then which of the following should be correct?

1. The entire tree is based on maximum parsimony.

2. If all species depicted here make up a taxon, this taxon is monophyletic.

3. The last common ancestor of species B and C occurred more recently than the last common ancestor of species D and E.

4. Species A is the direct ancestor of both species B and species C.

5. The species present at position 3 is ancestral to C, D, and E

#Question id: 9620

#Unit 9. Diversity of Life Forms

The two extant species that are most closely related to each other are

#Question id: 9619

#Unit 9. Diversity of Life Forms

A common ancestor for both species C and E could be at position number 

#Question id: 9617

#Unit 9. Diversity of Life Forms

The common ancestors of birds and mammals were very early (stem) reptiles, which almost certainly possessed 3-chambered hearts (2 atria, 1 ventricle). Birds and mammals, however, are alike in having 4-chambered hearts (2 atria, 2 ventricles). The 4-chambered hearts of birds and mammals are best described as

#Question id: 9615

#Unit 9. Diversity of Life Forms

In angiosperm plants, flower morphology can be very intricate. If a tree, such as a New Mexico locust, has flowers that share many morphological intricacies with flowers of the sweet pea vine, then the most likely explanation for these floral similarities is the same general explanation for the similarities between the

#Question id: 9614

#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). Consequently, the morphological similarities of these two species are probably due to