Listen to part of a lecture in a biology class.
- What is the lecture mainly about?
- A. How various proteins function in notothenioids.
- B. How notothenioids became the dominant type of fish in the Southern Ocean.
- C. An example that contradicts the theory of adaptive radiation.
- D. Changes in ocean habitats caused by continental drift.
- Why does the professor mention that coral reefs support more than 4,000 species of fish?
- A. To find out what students know about tropical fish.
- B. To contrast two types of ocean environments.
- C. To imply that there may be species in the Southern Ocean that have not been discovered yet.
- D. To imply that there may be fossil evidence of coral reefs in the Southern Ocean.
- What characteristic of notothenioids helps them survive in subfreezing temperatures?
- A. They maintain an unusually high body temperature.
- B. A special tissue in their eyes enables them to see through ice.
- C. Special proteins make their blood circulate too fast to freeze.
- D. Ice crystals in their bodies are prevented from growing large enough to harm them.
- Why did the antifreeze protein initially give no special advantage to the earliest notothenioids?
- A. Many other types of fish had the same protein.
- B. The notothenioids were not living in subfreezing temperatures.
- C. The effect of the antifreeze protein was neutralized by other proteins.
- D. The antifreeze protein functioned only in the smallest notothenioids.
- According to the professor, what factors led to the rapid distribution of notothenioids throughout the Southern Ocean?
[CHOOSE 2 ANSWERS]
- A. A genetic mutation occurred in the DNA of the earliest notothenioid.
- B. There was an increase in competition for food in temperate waters.
- C. Antarctica broke off and drifted away from the South American continent.
- D. The waters around Antarctica temporarily warmed up.
- According to the professor, what happened to notothenioids that migrated to different areas of the Southern Ocean?
- A. They evolved into a wide variety of notothenioid species.
- B. They developed the ability to tolerate a wide range of temperatures.
- C. Some of them became extinct because of new predators.
- D. Some of them developed additional antifreeze proteins.
B B D B AC A