Following statements are regarding to metastasis (using breast carcinoma cells as an example).

A. Cancer cells leave the main tumor and attack the basement membrane, using extracellular matrix (ECM) fibers to reach the blood vessels.

B. The cancer cells can be attracted by signals such as epidermal growth factor (EGF), which can be secreted by macrophages.

C. At the blood vessels they penetrate the layer of endothelial cells that forms the vessel walls and enter the bloodstream.

D. Carcinoma cells penetrate the extracellular matrix and blood vessel wall by extending “invadopodia,” which produce matrix metalloproteases and other proteases to open up a path.

Which of the following statement shows process of angiogenesis?

#Question id: 4649

#Unit 9. Evolution & Diversity of Life Forms

Which statement best describes the evolution of pesticide resistance in a population of insects?

#Question id: 4650

#Unit 9. Evolution & Diversity of Life Forms

DDT was once considered a ʺsilver bulletʺ that would permanently eradicate insect pests. Today, instead, DDT is largely useless against many insects. Which of these would have been required for this pest eradication effort to be successful in the long run?

#Question id: 4651

#Unit 9. Evolution & Diversity of Life Forms

Some members of a photosynthetic plant species are genetically resistant to an herbicide, while other members of the same species are not resistant to the herbicide. Which combination of events should cause the most effective replacement of the non-herbicide-resistant strain of plants by the resistant strain?

1. The presence of the herbicide in the environment

2. The absence of the herbicide from the environment

3. The maintenance of the proper conditions for one generation

4. The maintenance of the proper conditions for many generations

#Question id: 4652

#Unit 9. Evolution & Diversity of Life Forms

The graph depicts four possible patterns for the abundance of 3TC-resistant HIV within an infected human over time. If 3TC resistance is costly for HIV, then which plot (I—IV) best represents the response of a strain of 3TC-resistant HIV over time, if 3TC administration begins at the time indicated by the arrow?

#Question id: 4653

#Unit 9. Evolution & Diversity of Life Forms

 If two modern organisms are distantly related in an evolutionary sense, then one should expect that

#Question id: 4654

#Unit 9. Evolution & Diversity of Life Forms

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?