L3
讲座
1. What is the main purpose of the lecture?
To compare a domesticated plant and its wild relative
To explain the popularity of certain domesticated plants
To describe early North American farming techniques
To explore the differences between several varieties of domestic corn
2. What does the professor identify as a major source of human nutrition?
Plants that grow well in Central America
Plants that are easily pollinated
Domesticated animals that primarily eat grasses
Plants that are members of the grass family
3. What are some features of the teosinte plant?
It has soft kernels.
Its kernels are loosely attached to the stem.
Its pollen is easily carried by the wind.
Its kernels are covered by a husk.
4. Why does the professor mention corn’s husk?
To explain why it was difficult to domesticate corn
To question the usefulness of corn as a crop
To emphasize a feature of corn that resulted from its domestication
To explain why corn reproduces more successfully in the wild than teosinte does
5. What does the professor imply when she discusses the pollination of domesticated corn?
Corn pollen is smaller than teosinte pollen.
Domesticated corn reproduces without pollination.
Successful pollination of domesticated corn requires human help.
North American corn pollinates easier than corn grown elsewhere.
6. Why does the professor say this:
To fill in some details about the domestication of corn
To express her admiration for the developers of corn
To emphasize the importance of corn as a crop
To clarify a point about corn
