教材文本 Unit 4 Reading and Discussing的练习

Unit 4 Exploring plants2 Now read the text and answer the questions. 1 What is the advantage for animals of visiting flowers?2 Why do some plants need animals?3 How does an animal pollinate a flower?4 What features of a flower are important in attracting animal pollinators?5 What is nectar?6 What kinds of animals arc most flowers pollinated by?3 Are these statements true or false?True Falsel Bees follow coloured lines to the nectar inside the flower. 2 Flowers that are white or pale can be seen by night pollinators. 3 Butterflies are attracted to sweetsmelling flowers. 4 Bats pollinate flowers at night. 5 Flower colour is not important to hummingbirds. 6 All pollinators need to land on the flower if they are to find the nectar. 4 Find other nouns in the chart that mean the same as “smell”. List adjectives from the chart that are used to describe different kinds of smells. Nouns that mean “smell”: _ Adjectives that describe smells: _5 In groups, look at the pictures and decide what kinds of pollinators these plants might have. Give reasons for your answers. Answer key for Exercise 1：The text is about flowers and their animal pollinators. The pictures show different kinds of animal pollinators and their flowers. The chart lists animal pollinators and the characteristics of the flowers they pollinate. Suggested answers to Exercise 2：1 Animals get food called nectar from the flowers. 2 Some plants need animals to pollinate them. 3 An animal pollinates a flower by collecting pollen from a flower and passing it onto another flower. 4 The features of a flower that are important in attracting animal pollinators are its colour, shape, size and smell. 5 Nectar is a sweet liquid produced by flowers and collected by bees. 6 Most flowers are pollinated by bees, moths and butterflies. Answer key for Exercise 3：1 T 2 T 3 F 4 T 5 F 6 FAnswer key for Exercise 4：Nouns that mean “smell”：odour perfumeAdjectives that describe smells：delicate, fragrant, odourless, strong, sweet, musty, fruitySuggested answers to Exercise 5：Note：Students do not need to know the names of the flowers that are featured on page 39 but for your information, their English names are：A cactus flowers B fuchsiasC Peruvian lilies D unidentified purple flowersE chrysanthemums F hibiscusG wild ginger flower H Johnny jump upsA Bats, moths It is hard to tell what size these flowers are but if they are large, then bats might pollinate them. The flowers mouths look wide enough for bats and they are white so bats could see them at night. As these flowers are white they could possibly be pollinated by moths. However, the petals do not look as though they form a deep tube for the moths tongues. In addition, the petals do not lie flat or bend back so the moths may not be able to get close to the flowers. （We do not know whether the flowers have a scent. ）B Hummingbirds Hummingbirds might be the pollinators of these flowers as they are red and have long tubes. The petals look very short so the birds could get close to the flowers. The birds could hover below the flowers while drinking the nectar with their long thin beaks. C Bees The flowers are bright yellow and have brown lines on the petals that bees would use to guide them to the nectar. The petals are wide enough for bees to land on. D Hummingbirds, butterflies Because these purple flowers have long tubes and a landing place, we can imagine that butterflies might pollinate them. The tube looks too long for bees tongues. Hummingbirds might visit these flowers because they tilt downwards and so would allow the birds to hover while putting their beaks into the long tubes. E Butterflies Butterflies could be the pollinators of these flowers as they are red and each has a place in its centre for butterflies to land on. F Butterflies, hummingbirds This flower could attract butterflies because it is red and the petals are wide enough for the butterflies to land on. Hummingbirds might visit this flower also because of its colour and because the petals are bent back a little so that the birds could get close. G Flies The flowers on this plant are not obvious as they are near the ground and are also dark red. Therefore, they probably wouldnt attract insects that like bright colours. Although we dont know, it is likely that these flowers have a strong smell like rotting meat. These flowers might be pollinated by fl