Walk through Times Square—you’re bombarded with advertising. And it turns out, a bumblebee might have a similar feeling, buzzing through a field of flowers. "So these flowers are these billboards, they’re advertising a commodity, this delicious nectar (花蜜) reward, and bees are very picky shoppers," says Anne Leonard, a pollination (授粉) biologist at the University of Nevada, Reno. She describes a flower field as a sort of pollination marketplace. "Bees are nectar experts. They are really good at assessing even really small differences in the sugar concentration of nectar." They also scope out flower shape and size, color and scent. And now Leonard and her colleagues have discovered that bumblebees are also sensitive to pollen.They found that out by lacing batches of cherry pollen with either table sugar or bitter quinine. And to display the pollen to bees, "We got really into it—we started 3-D printing flowers in our lab." And for the anther—the male flower part, which presents the pollen—pipe cleaners. "So we bought out Michael’s craft store supplies of these pipe cleaners and used them in our experiments."It turns out bees would return again and again to the same color flower that dispensed sweet pollen, and spend more time collecting there. But when confronted with the bitter pollen, they sought a different colored flower for their very next stop. All of which suggests that, in addition to savoring nectar, bees taste pollen too—and judge flowers by it. The results are in the journal Biology Letters.The finding means that plants have to find a happy medium: "So can you make your pollen attractive enough that the bees will collect it, but distasteful enough that they won’t collect too much of it?" And that balancing act, of carefully calibrated chemistry (校准化学)—it’s just one of the many transactions that plays out in the buzzing pollination marketplace, where the object is to make a sweet profit.1. What does the author compare a flower field to?A) Times Square. B) A commodity.C) A billboard.D) A shopper.2. Why are bees described as nectar experts?A) Because they are able to detect differences in sugar levels of nectar. B) Because they are capable of discerning different types of flowers.C) Because they know instinctively where to collect more nectar.D) Because they could distinguish sweet pollen from bitter one.3. What are used to present the pollen by Anne and her colleagues in their experiments?A) 3-D printers.B) Pipe cleaners. C) Sugar.D) Quinine.4. How do bees choose where to visit in a flower field according to the passage?A) By color and scent of flowers.B) By taste of nectar and pollen. C) By maleness or femaleness of flowers.D) By shape and size of flowers.5. What do Anne and her colleagues’ research findings suggest?A) Calibrated chemistry is very useful in changing the structure of pollen.B) Attracting more bees to pollinate could make plants more productive.C) The more bees to be attracted, the better it will be for the pollen.D) The taste of pollen can be controlled for commercial purpose.

Walk through Times Square—you’re bombarded with advertising. And it turns out, a bumblebee might have a similar feeling, buzzing through a field of flowers. "So these flowers are these billboards, they’re advertising a commodity, this delicious nectar (花蜜) reward, and bees are very picky shoppers," says Anne Leonard, a pollination (授粉) biologist at the University of Nevada, Reno.   She describes a flower field as a sort of pollination marketplace. "Bees are nectar experts. They are really good at assessing even really small differences in the sugar concentration of nectar." They also scope out flower shape and size, color and scent. And now Leonard and her colleagues have discovered that bumblebees are also sensitive to pollen. They found that out by lacing batches of cherry pollen with either table sugar or bitter quinine. And to display the pollen to bees, "We got really into it—we started 3-D printing flowers in our lab." And for the anther—the male flower part, which presents the pollen—pipe cleaners. "So we bought out Michael’s craft store supplies of these pipe cleaners and used them in our experiments." It turns out bees would return again and again to the same color flower that dispensed sweet pollen, and spend more time collecting there. But when confronted with the bitter pollen, they sought a different colored flower for their very next stop. All of which suggests that, in addition to savoring nectar, bees taste pollen too—and judge flowers by it. The results are in the journal Biology Letters. The finding means that plants have to find a happy medium: "So can you make your pollen attractive enough that the bees will collect it, but distasteful enough that they won’t collect too much of it?" And that balancing act, of carefully calibrated chemistry (校准化学)—it’s just one of the many transactions that plays out in the buzzing pollination marketplace, where the object is to make a sweet profit.1. What does the author compare a flower field to?A)  Times Square. B)  A commodity.C)  A billboard.D)  A shopper.2. Why are bees described as nectar experts?A)  Because they are able to detect differences in sugar levels of nectar. B)  Because they are capable of discerning different types of flowers.C)  Because they know instinctively where to collect more nectar.D)  Because they could distinguish sweet pollen from bitter one.3. What are used to present the pollen by Anne and her colleagues in their experiments?A)  3-D printers.B)  Pipe cleaners. C)  Sugar.D)  Quinine.4. How do bees choose where to visit in a flower field according to the passage?A)  By color and scent of flowers.B)  By taste of nectar and pollen. C)  By maleness or femaleness of flowers.D)  By shape and size of flowers.5. What do Anne and her colleagues’ research findings suggest?A)  Calibrated chemistry is very useful in changing the structure of pollen.B)  Attracting more bees to pollinate could make plants more productive.C)  The more bees to be attracted, the better it will be for the pollen.D)  The taste of pollen can be controlled for commercial purpose.