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Deadly plants

The tree of death

Malaysian people frightened the first European visitors to their land with tales of the deadly upas tree. They called it the tree of death. They said that the tree killed birds flying over it and that anyone who slept in its shade would never wake up.

Seven hundred years later we know that their stories are untrue. Birds sit unharmed in the tree’s branches and sleeping under the tree is perfectly safe.

However, the sap of the tree contains a deadly poison. A scratch from the bark causes a painful rash. Poison taken from the sap can stop the heart from beating in just a few minutes.

Local people once executed prisoners by tying them to the tree, or by stabbing them with a stick dipped in the poison.

     

The candelabra tree

The candelabra tree gets its name from its unusual shape. If it were smaller it would look like a candelabra, or candle stand. However, candelabra trees are not small. They are huge. In South Africa, where they grow wild, candelabra trees may reach the height of a house.

The candelabra tree contains milky sap that can burn your skin and even cause blindness if it gets in your eyes.

In some areas, the parents of twins plant a pair of the trees in front of their home to mark the birth. They believe that the trees will scare off evil spirits and protect the children. Nobody dares cut down these trees, even when the home is gone and the twins are long dead.

     

 

 

Deadly curare

In the depths of the Amazon rainforest grow thousands of bushes, vines and trees. Here, the native people found the ingredients to make one of the world’s most powerful natural poisons; curare.

The native people used the poison to hunt animals. To get the poison, they soaked the bark and roots of certain plants in water, then boiled the water to make a paste. They smeared the paste on small darts and shot the darts from long bamboo blowpipes.

The hunters shot monkeys to test the poison. If the monkey fell quickly from a tree, the poison was ‘one-tree’ poison – the strongest. If the monkey jumped to another tree before falling, the poison was ‘two-tree’ poison.

 

Beautiful but poisonous

Many dangerous plants are quite beautiful. You would never guess from its pretty blue flowers that the monks’-hood contains a powerful poison. The name of the poison is aconitine and even small amounts of it can kill. The roots, leaves, stems, and even the flowers of the monks’-hood are poisonous!

In Italy, hundreds of years ago, murderers gave their enemies gloves dusted with aconitine powder. The poison entered the victims’ bodies through cuts or scratches on their fingers.

aconitine [,ækənı´ti:n] –; amount [ə´maunt] – stem –;   enemy [´enəmı] –; powder [´paudə] –; victim [´vıktım] – monks’-hood -

Deadly seeds

Like the monks’-hood, the bright red seeds of the rosary pea plant look harmless. People in India used the seeds to make necklaces and rosaries.



But wearing such a necklace is a bad idea. Each little seed contains enough poison to kill an adult. If the outer casing of the seed is broken or cracked, the poison inside escapes. It can enter the body through a scratch or cut.

rosary pea [´rəuzərı ,pi:] – àáðóñ îïàñíûé, ÷åòêîâûé ãîðîõ; necklace [´vıktım] – îæåðåëüå; rosary [´rəuzərı] – ÷åòêè;   outer casing [,autə ´keısıŋ] – âíåøíÿÿ îáîëî÷êà; to escape [ı´skeıp] – óáåãàòü, âûòåêàòü.

 

 

EAKING

Exercise 1. Answer the questions with more than one sentence.

1. Do you use medicinal plants to keep yourself healthy? Which ones?

2. For what purposes have people selected and bred plants?

3. Would you name the flowers the modern perfume industry uses for the purest fragrances? Would you name some of natural cosmetic products?

4. Many of the early botanists were also doctors. Why do you suppose this is no longer so?

Exercise 2. Fulfill the following tasks.

a) Enumerate: plants which are harvested a) in spring b) in summer c) in autumn. Which parts of the enumerated plants are usually used in medical practice?

b) Indicate: some spices and medicines obtained from a) roots or rhizomes b) stems c) leaves d) flowers.

c) Briefly Indicate: contributions to plant science made by the ancient Egyptians and the Chinese.

Exercise 3. Look through the list of plants in Appendix part of the textbook and choose any of the flowering plant. Think of a description and present it to your group mates to guess the name of the plant described.

Exercise 4. Give your recommendations a) for dealing with wild plants; b) for storing dried medicinal plants.

Use the following phrases: you should (shouldn’t) do something; you’d better (you’d better not) do something; it’s (isn’t) advisable to do something; it’s (isn’t) recommended to do something.

Exercise 5. Act out the following situation.

You are giving emergency help for the victim of poisoning. Before rendering help ask the victim 1) what plant he was in contact with 2) what complaints the victim has.

Use the following word combinations: skin irritation, reddening of the affected area, dryness in the mouth, to induce vomiting, to wash clothing, to make the victim drink some water, to consult a doctor.

 

 

Exercise 6. Speak on the following.

1. Herbal medicines as a source of natural drugs.

2. Best time for harvesting medicinal plants.

3. Rules for storing dried plant material.

4. Description of drugs of plant origin by odour and taste.

5. Therapeutic effects of some medicinal plants.

6. Poisonous plants and their effects.

 

 

Sypplementary texts

DID YOU KNOW THAT … ,

• Lower-class people hardly ever changed or washed their clothes. Most of them only had one outfit for working and one for Sunday. Wealthy clothes were cleaner because they owned more outfits. As you can imagine, people must not have smelled very sweet, but they were used to (ïðèâûêëè) body odour. Wealthy men and women sprinkled themselves (îáðûçãèâàëè ñåáÿ) with lavender water or wore small bouquets of flowers called nosegays (áóêåòèêè öâåòîâ) to put a sweet smell near their nose.

• Today everybody knows that tobacco is dangerous. But in the 1600s English doctors prescribed tobacco as a cure (ìåòîä ëå÷åíèÿ) for numerous diseases including plaque (÷óìà).

• Coffee originated in the Middle East more then one thousand years ago. Since then people have used it as food, medicine and wine. Coffee beans are used as currency (âàëþòà) in some isolated parts of Africa, and the failure (íåñïîñîáíîñòü) of a Turkish husband to provide his wife with coffee was once considered as “ground for divorce (ðàçâîä).

• Because pod-shaped fruits of cacao were believed to be of a divine origin (áîæåñòâåííîãî ïðîèñõîæäåíèÿ), botanist Carolus Linnaeus named the plant Theobroma, meaning “food for the gods”.

• The Giant water lily from Amazon is the world’s largest water plant. It leaves can grow up to ten meters and they are strong enough to take the weight of a child.

• The largest flower on Earth comes from a tropical forest. It’s Rafflesia arnoldi and it grows up to one meter across. This parasitic plant is also one of the worst-smelling flowers on Earth.

• The smelliest flower on Earth is the Amorphophallus titanium, popularly known as the corps (òðóïíîå) flower. It blooms only a few times in its 40-year life-span (ïðîäîëæèòåëüíîñòü æèçíè), but when it dies it smells of what has been variously described as similar to that fo rotting egs, a dead animal and worse. This smelly plant is taller than a man and can be found in Indonesia and in some botanical gardens.

• Many jungle trees have flowers that sprout (ðàñòóò) straight out of their trunks.

• Baobab trees become fatter or thinner depending on the weather. When it rains, the roots drink the water and the tree stores it in the trunk. During the long dry season the tree becomes thinner and thinner as it uses up its store of water.

• The first plant to flower in zero gravity of space (íåâåñîìîñòü) was Arabidopsis. It was grown on board Russia’s Salute-7 space station in 1982.

Test.

Read the passage about plant essential elements and retell it.


Date: 2014-12-22; view: 1263


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