141 water bear the space survivor

pushing children certain conditions scientists’ interest name destroy eat biggest sg is true by sg water conditions WATER BEARS: THE ANIMAL THAT SURVIVED SPACE!. Water bears, also known

Task 1 Label the

paragraphs with their topic.

1 Significance of water bears

2 The Experiment

3 Objective of Experiment

4 Who Are Tardigrades

5 Results of Experiment

Task 2 Find synonyms in

the text for the phrases.

pushing

children

certain conditions

scientists’ interest

name

destroy

eat

biggest

sg is true

by sg

water

conditions

WATER BEARS:

THE ANIMAL THAT

SURVIVED SPACE!

Meet a hardy little organism

called the water bear.

Water bears, also known as tardigrades, are a

wonder! They are tiny eight-legged creatures, known for their virtual indestructibility on Earth

They can survive almost anything: extreme

temperatures, tons of radiation, the pressures

of the deep sea, starvation, and nearly a decade without water Now their legendary toughness has been put to the ultimate test They've been

sent into space!

In the past, some biologists have suggested that tardigrades may be

the only animal to come back alive after a trip in real space Scientists

now decided to send them into space to find out if that is true

Once in space, all the water bears were exposed to the vacuum of

space, and some were even exposed to solar and cosmic radiation

After 10 days of exposure to space, the satellite returned to Earth The

water bears were rehydrated to see how their reproductive abilities

were affec ted.

The vacuum itself seemed to have little effect on the creatures But

ultraviolet radiation , which can damage cellular material and DNA, did

take its toll Yet, a handful of animals even survived full exposure to

the Sun's UV light, which is more than 1000 times stronger in space

than on the Earth's surface

Water bears are a mystery They have an unparalleled ability to cope

with the extremely dry conditions of deep vacuum and the harmful

solar and cosmic radiation up there, which has piqued scientific

curiosity Still, no one quite understands how they can be as resistant

as they are Besides, they are also challenging our traditional

concepts of life, for instance that life depends on water, or that life is a

continuous process

TARDIGRADE QUIZ

I Are water bears bacteria or animals?

A They have claws and eyes They are real animals

B They are bacteria

C Neither, they are the largest known viruses

II How big are they?

A Tardigrades are about the size of a fly

B Bigger adults are visible to the naked eye, reaching about 1,5 mm in length

C They can only be seen under a microscope

III How many legs do they have?

A Tardigrades are six-legged

B Tardigrades are seven-legged

C Tardigrades are eight-legged

IV Where do they live?

A They are found throughout much of Asia and Africa

B Tardigrades occur over the entire world, from the high Himalayas (above 6,000 m), to the deep sea (below 4,000 m) and from the polar regions to the equator

C They can only be found inside active volcanos in Peru

V How did they get their name?

A The name water bear comes from the way they walk, reminiscent (=reminding) of a bear's

B The name is a reminder of their distant genetic relationship with bears

C The name reflects their ability to go into hibernation to survive extremes

VI How hot is too hot for them?

A They can survive temperatures between -50 and 90 °C for a few minutes

B They can survive temperatures between -150 and 125 °C for a few minutes

C They can survive being chilled to –272 °C (absolute zero is −273.15 °C), or being heated to 151 °C for a few minutes

VII How long can they go without water?

A Tardigrades can go without water for nearly one year

B Tardigrades have been shown to survive nearly one decade in a dry state

C Tardigrades can survive nearly one hundred years in a dry state

VIII How much radiation can they survive?

A They can withstand (=survive) 17,000 rads of x-ray radiation (1,000–2,000 rads could be fatal to a human)

B They can withstand 57,000 rads of x-ray radiation

C They can withstand 570,000 rads of x-ray radiation

IX How do they survive extreme conditions?

A They're capable of halting (=stopping) their metabolisms (=life functions) during times of extreme privation (=a lack of basic things), and can repair DNA damage caused by extraordinary doses of radiation

B They are supposed to be alien organisms that landed on Earth with an incoming meteor Their native planet must have been much closer to the Sun, making them evolve resistance toward extreme heat and radiation

C They survive extremes by having a tremendously resilient (=resistant) shield that reflects heat and radiation

Source URLs:

http://tardigradesinspace.blogspot.com/

http://blog.wired.com/wiredscience/2008/09/invertebrate-as.html

http://www.newscientist.com/article/dn14690?DCMP=ILC-hmts&nsref=news1_head_dn14690

http://en.wikipedia.org/wiki/Tardigrade

http://x1brettstuff.blogspot.com/2007/10/tardigrades-in-space.html

TARDIGRADE QUIZ

SOLUTIONS

I Are water bears bacteria or animals?

A They have claws and eyes They are real animals

II How big are they?

B Bigger adults are visible to the naked eye, reaching about 1,5 mm in length

III How many legs do they have?

C Tardigrades are eight-legged

IV Where do they live?

B Tardigrades occur over the entire world, from the high Himalayas (above 6,000 m), to the deep sea (below 4,000 m) and from the polar regions to the equator

V How did they get their name?

A The name water bear comes from the way they walk, reminiscent of a bear's

VI How hot is too hot for them?

C Tardigrades can survive being chilled to –272 °C (absolute zero is −273.15

°C), or being heated to 151 °C for a few minutes

VII How long can they go without water?

B Tardigrades have been shown to survive nearly one decade in a dry state

VIII How much radiation can they survive?

C They can withstand 570,000 rads of x-ray radiation (1,000–2,000 rads could

be fatal to a human)

IX How do they survive extreme conditions?

A They're capable of halting their metabolisms during times of extreme privation, and can repair DNA damage caused by extraordinary doses of radiation

Source URLs:

http://tardigradesinspace.blogspot.com/

http://blog.wired.com/wiredscience/2008/09/invertebrate-as.html http://www.newscientist.com/article/dn14690?DCMP=ILC-hmts&nsref=news1_head_dn14690

http://en.wikipedia.org/wiki/Tardigrade http://x1brettstuff.blogspot.com/2007/10/tardigrades-in-space.html

COMPREHENSION QUESTIONS

ARTICLE & QUIZ

1 Why did scientists send water bears into space?

………

2 What was more difficult for water bears to survive: vacuum or cosmic radiation?

………

3 How does the existence of water bears inform our understanding of what “life” is?

………

4 How long can water bears go without water?

………

5 How did tardigrades get their names?

………

6 Are tardigrades real animals?

………

7 What do scientists understand about how these creatures can survive such extremes that no other animal can?

………

VOCABULARY PRACTICE

1 a force of pushing ………

2 a lot of UV waves ………

3 ability to create children ………

4 being faced with certain conditions ………

5 decade ………

6 do harm to sg ………

7 having a second name ………

8 having eight legs ………

9 having no rivals ………

10 having nothing to eat ………

11 idea ………

12 impossibility to destroy ………

13 the best or the biggest ………

14 to be influenced by sg ………

15 to be soaked in water ………

16 to excite scientists’ interest ………

17 to face certain conditions ………

18 to find the answer ………

19 to question that sg is true ………

20 to survive ………

21 to tackle sg ………

22 to test ………

23 tough (2.) ………

24 tough ………

25 very famous ………

SOLUTIONS

Task 1 Label the paragraphs with their topic.

1 Who Are Tardigrades

2 Objective of Experiment

3 The Experiment

4 Results from Experiment

5 Significance of water bears

Task 2 Find synonyms in the text for the phrases.

Vocabulary

1 a force of pushing: pressure

2 a lot of UV waves: tons of radiation

3 ability to create children: reproductive abilities

4 being faced with certain conditions: exposure to

5 decade: 10 years

6 do harm to sg: take its toll

7 having a second name: also know n as

8 having eight legs: eight=legged

9 having no rivals: unparalelled

10 having nothing to eat: starvation

11 idea: concept

12 impossibility to destroy: indestructibility

13 the best or the biggest: ultimate

14 to be influenced by sg: be affected

15 to be soaked in water: rehydrate

16 to excite scientists’ interest: piqued scientific curiosity

17 to face certain conditions: be exposed to

18 to find the answer: find out if …

19 to question that sg is true: challenge

20 to survive: come back alive

21 to tackle sg: cope with

22 to test: put to the test

23 tough: hardy

24 tough (2.): resistant

25 very famous: legendary