#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?
#Question id: 4655
#Unit 9. Evolution & Diversity of Life Forms
Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?
#Question id: 4656
#Unit 9. Evolution & Diversity of Life Forms
Logically, which of these should cast the most doubt on the relationships depicted by an evolutionary tree?