普通高中课程标准实验教科书 英语选修9 Unit 4 Exploring plants(在线收听) | ||||||||||||||
Reading and discussing
Before you read the text on page 38, have a quick glance at it. What is the text about? What do the pictures show you? What is the chart about?
FLOWERS AND THEIR ANIMAIL POLLINATORS
Over time, many flowering plants and their animal pollinators have evolved together. The plant needs the animal to pollinate it and the animal is rewarded with food called nectar when it visits the flowers. Pollen becomes attached to the animal during its visit to a flower and is then passed on to another plant's blossom on its next visit. So pollination takes place, therefore increasing the chances of the survival of the plant species.
Through evolution, most flowers have adapted to attract specific types of pollinators. Bees, moths and butterflies are the most important
pollinators. Flies, wasps, beetles and other animals such as birds and bats are less common.
The type of pollinator depends on the characteristics of the flower such as its colour, shape, size and smell. For example, yellow flowers attract bees, while red flowers attract butterflies. The nectar in some flowers can only be reached by a bird with a long bill or a long-tongued moth or butterfly. The chart below describes some features of flowers that attract certain kinds of pollinators.
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