unit 4 exploring plants reading task课件

课件24张PPT。Reading on P78Co–Evolution yucca 丝兰yucca moth The Traveller’s
Palm 棕榈树The Madagascar black lemurThe Ophrys Orchid 兰花waspWarming up Discuss the question:
What’s the relationship between
plants and animals?Pre-reading Before you read the text, glance quickly
through it and answer these questions.
1. What’s the topic of the text?
2. What three plants are featured?
3. What do the photos show you?
4. What three animal pollinators are
featured?What’s the topic of the text?2. What three plants are featured?Co-evolution. The yucca, the Traveller’s Palm, and the Ophrys orchid.3. What do the photos show you?4. What three animal pollinators are featured?Yucca flowers, a Traveller’s Palm,
and an Ophrys orchid. The yucca moth, the Madagascar
black lemur, a certain kind of wasp
(the male, not the female wasp).First reading Now read the text more carefully and
answer these questions.Why can no other animals but the
yucca moth pollinate the yucca? It’s only the yucca moth which is
the right size and shape to pollinate
the yucca.2.Can you guess why the Traveller’s
Palm has that name? The Traveller’s Palm has this name
because travellers used to drink
its nectar when they were thirsty.3. What do you think “sweet tooth”
means? If a person or an animal has a “sweet tooth”, they like sweet food very much.4. Why do the male wasps try to mate with the orchid flowers? The male wasps try to mate with
the orchid flowers because they
look like and smell like female wasps. 5. Why do the female wasps visit the orchid flowers? Do they have a role in pollination? The female wasps visit the orchid
flowers to collect the chemical that the male wasps were attracted to earlier. The female wasps do not have a role in pollination since the flowers are dying when they visit them.Second reading Now read and think about the advantages and disadvantages of the relationships between the plants and pollinations described in the text.
Check your understanding and complete the table.The yucca is certain to be pollinated.
The moth’s caterpillars have a certain supply of foodThey are totally dependent on each other for survival.
The palm’s flower can be opened by the lemur.
The lemur has a source of food.There is a disadvantage for the palm only if there are no lemurs or other animals present strong enough to open the flowers.The orchid is certain to be pollinated.They are totally dependent on each other for survival.The female wasps collect a chemical from the orchid needed to attract the males to them.Discussion Discuss what you think would happen
to the animal pollinators of each of
the plants described if these plants
died out.Suggested answers:The yucca and the yucca moth:
If yucca plants died out, the
Yucca moth would also die out as the caterpillars need the yucca seeds for food. The Traveller’s palm and the
Madagascar black lemur:
If the Traveller’s palm died out,
the Madagascar black lemur would
not die out as it can find other sources of food. The Ophrys orchid and the wasp:
If the Ophrys orchid died out, the wasp would also died out as the
female wasp needs the chemical
produced by the orchid to attract
the male wasps.