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Script:

A botanist has been invited to speak to a geography class. She will be discussing aromatic trees of North America. Listen to part of the talk.

When European explorers first approached the coast of North America, even before their ships landed, the first thing they noticed was the pungent aroma carried to the ships by the offshore breezes. Some sea captains thought this aroma was the scent of the valuable Oriental spices that had prompted their voyages of exploration. But in fact, the agreeable smells didn’t come from spices: they came from the lush vegetation of the North American forests.

The fragrance came from the blossoms of numerous trees and from the volatile oils in pine sap. Pine sap is a resinous fluid that pine trees put out to heal wounds caused by wind, fire, and lightning, and also to protect the pine tree’s seeds.

Pine sap was a valuable commodity to the sailors who explored the coast. The smell of pine meant there was an abundant supply of what were known as naval stores pitch and pine tar. Pitch and pine tar were thick, sticky, semi-solid substances that were made by distilling pinewood. Sailors used naval stores for caulking and waterproofing their wooden ships, which kept them seaworthy.

The Europeans found fragrant trees all along the Atlantic coast, from Massachusetts in the north to Florida in the south. Everywhere along the coast, the air was filled with the strong perfume of the flowering dogwood. The Native Americans already knew about the medicinal properties of the dogwood, and they used its bark and roots to treat malaria and other fevers. They brewed the aromatic bark into a bitter, astringent tea. European settlers also used the dogwood to relieve attacks of malaria. They soaked the dogwood bark in whiskey and drank the strong infusion. This was before they knew’ about quinine from South America, and before quinine became available.

In the south, probably the best-known aromatic tree was the sassafras. The sassafras is a fast growing tree, a member of the laurel family. Like the other fragrant laurels cinnamon, bay. and camphor sassafras is noted for its aromatic bark, leaves, roots, flowers, and fruit. I have a sassafras twig with me here, which I′ll pass around so you can all enjoy its smell. Just give it a small scrape with your thumbnail to release the scent.

I think you’ll find it strong but pleasant.

The Choctaw Indians used powdered sassafras leaves as a spice. Other Native American tribes used sassafras tonic as a cure for everything from fever to stomachache. News of this wonder tree reached Europe in the sixteenth century by way of the French and the Spanish, and sassafras was one of the first exports from North America to Europe. It sold for a high price on the London market, which sort of inspired other English explorers to ... um ... seek their fortunes in the North American colonies.

For centuries, sassafras enjoyed a fantastic reputation as a cure for almost every disease. Maybe you′ve heard of the medicinal spring tonic of the old days. Well, sassafras was a main ingredient in spring tonic—the stuff pioneer parents gave their kids. My grandmother had to take the spring tonic that her grandmother made from sassafras.

Sassafras leaves, bark, and roots used to provide the flavoring for root beer and chewing gum. Sassafras was also used in soaps and perfumes. However, in the 1960s, the United States Food and Drug Administration found sassafras oil to be a potential carcinogen for humans because it caused cancer in rats. Since that time, sassafras has been banned for human consumption. No one really knows just how harmful it is to human beings, but some studies show that one cup of strong sassafras tea contains more than four times the amount of the volatile oil safrole that is hazardous to humans if consumed on a regular basis.

4. Why does the speaker say this?

A.

She needs someone to help her lift a heavy tree.

B.

She is demonstrating how to brew tea.

C.

She is giving a recipe for a medicinal tonic.

D.

She wants the students to smell a piece of wood.

5. Why was sassafras once considered a wonder tree?

A.

Its fragrance was the sweetest of any American tree.

B.

Its sap could be made into a tar to seal wooden ships.

C.

It was thought to be a cure for almost every disease.

D.

It provided more board timber than any other tree.

6. Listen again to part of the talk. Then answer the question. What does the speaker imply about sassafras?

A.

It is too expensive for most people.

B.

It is no longer a legal medicine.

C.

It is available only in drugstores.

D.

It is probably not harmful to humans.

Script:

Listen to part of a lecture in a geology class.

Mount St. Helens is in the Cascade Range, a chain of volcanoes running from southern Canada to northern California. Most of the peaks are dormant what I mean is, they’re sleeping now, but are potentially active. Mount St. Helens has a long history of volcanic activity, so the eruptions of 1980 weren′t a surprise to geologists. The geologists who were familiar with the mountain had predicted she would erupt.

The eruption cycle had sort of a harmless beginning. In March of 1980, seismologists picked up signs of earthquake activity below the mountain. And during the next week, the earthquakes increased rapidly, causing several avalanches. These tremors and quakes were signs that large amounts of magma were moving deep within the mountain. Then, suddenly one day there was a loud boom, a small crater opened on the summit. St. Helens was waking up.

The vibrations and tremors continued. All during April, there were occasional eruptions of steam and ash. This attracted tourists and hikers to come and watch the show. It also attracted seismologists, geologists, and—of course -the news media.

By early May. the north side of the mountain had swelled out into a huge and growing bulge. The steam and ash eruptions became even more frequent. Scientists could see that the top of the volcano was sort of coming apart. Then there were a few days of quiet, but it didn’t last long. It was the quiet before the storm.

On the morning of May 18—a Sunday at around eight o’clock, a large earthquake broke loose the bulge that had developed on the north face of the mountain. The earthquake triggered a massive landslide that carried away huge quantities of rock. Much of the north face sort of swept down the mountain.

The landslide released a tremendous sideways blast.

Super heated water in the magma chamber exploded, and a jet of steam and gas blew out of the mountain’s side with tremendous force. Then came the magma, sending up a cloud of super-heated ash. In only 25 seconds, the north side of the mountain was blown away. Then, the top of the mountain went too, pouring out more ash, steam, and magma. The ash cloud went up over 60.000 feet in the air. blocking the sunlight.

Altogether, the eruptions blew away three cubic kilometers of the mountain and devastated more than 500 kilometers of land. The energy of the blast was equivalent to a hydrogen bomb of about 25 megatons. It leveled all trees directly to the northeast and blew all the water out of some lakes. The blast killed the mountain′s goats, millions of fish and birds, thousands of deer and elk and around sixty people. The ash cloud drifted around the world, disrupting global weather patterns.

For over twenty years now. Mount St. Helens has been dormant. However, geologists who’ve studied the mountain believe she won’t stay asleep forever. The Cascade Range is volcanically active. Future eruptions are certain and— unfortunately we can’t prevent them.

7. According to the professor, how did the cycle of volcanic eruptions begin?

A.

Magma poured out of the top of the mountain.

B.

A cloud of ash traveled around the world.

C.

The volcano erupted suddenly without warning.

D.

Several earthquakes and avalanches occurred.

8. Why does the professor say this:

A.

To tell of his own experience of watching the mountain

B.

To explain why the events were a surprise to geologists

C.

To show that the eruptions interested a lot of people

D.

To criticize the media for interfering with the scientists

9. Listen again to part of the lecture. Then answer the question.

What does the professor mean when he says this:

A.

Scientists took a few days off before continuing their work.

B.

The public suddenly lost interest in watching the eruptions.

C.

The small eruptions paused briefly just before the major eruption.

D.

It had been a long time since the previous eruption of St. Helens.

10. What can be concluded about Mount St. Helens?

A.

It is a harmless inactive volcano.

B.

It is no longer of interest to geologists.

C.

It is likely to erupt in the future.

D.

It is the largest volcano in the world.

11. What were some effects of the eruption? Click on TWO answers.

A.

Geologists were criticized for failing to predict it.

B.

Tourists were afraid to visit the Cascade Range.

C.

The ash cloud affected weather around the world.

D.

Large numbers of animals and people were killed.

12. The professor explains what happened when Mount St. Helens erupted. Choose THREE sentences were part of the event.

A.

The mountain gained sixty feet in height.

B.

Ash and steam rose from the mountain.

C.

An earthquake caused a huge landslide.

D.

The mountain's side and top exploded.

Script:

Listen to a lecture in a zoology class.

Today, we’ll be talking about how different types of animals hear. Many animals have sense organs that allow them to process sound waves. However, the sense organs are structured and function in very different ways in different types of animals.

First, we’ll look at the hearing abilities of some examples of insects and amphibians. Let’s look now at an example of an insect. A cricket’s a type of insect, and it has thin membranes that vibrate when sound hits them. The thin “hearing’’ membranes on a cricket are found on the side of each front leg. On other insects, these vibrating membranes can be found on various other body parts.

Now, let’s look at an example of an amphibian. . . . The frog’s a good example of one. The frog has large disks that serve as eardrums. These disks are located farther back on the head, behind each eye. The disks, or eardrums, behind each eye vibrate when sound hits them. So you see that the frog has large disks on its head that serve as eardrums, unlike the cricket that I talked about earlier, which is able to hear by means of vibrating membranes on the side of each front leg.

Now, let’s look at the hearing of birds and bats. Birds have external auditory canals along the sides of the head. The auditory canal on a bird is merely an opening that leads to the middle and inner ear, and this auditory opening on a bird is usually covered with feathers.

Birds lack auricles, which are external portions of the ear that protrude from the body.

Bats are not birds; they′re mammals. And like most mammals, they have auricles. You can see the large auricles on the bat, the part of the ear that protrudes from the bat’s head. Bats are dependent on their hearing to navigate in the dark; they have very effective auricles that move to enhance their ability to pick up sound waves as they enter the ear. So we’ve seen that birds and bats have different ways of hearing because bats are mammals so they have auricles. But birds are not mammals, so they don’t have auricles. They have auditory canals instead.

Now, let’s look at some other types of mammals, the elephant and the rabbit. Mammals are the only animals that have auricles, and elephants and rabbits are mammals, so they have auricles.

The auricles of the African elephant are the largest of any animal, and rabbits have auricles that are unusually large in proportion to their bodies. These large auricles allow heat to escape the body and assist these animals in cooling off in hot weather.

Now let me switch gears and talk for a moment about echolocation. Some animals are dependent on their hearing to navigate in the dark. The process that they use is called echolocation. Animals that use echolocation produce sounds and then listen for echos as the sound waves they have produced are reflected off of objects around them. They use echolocation to determine when objects are in their path and how far away the objects are. Bats and whales are two animals that navigate using echolocation, and there are many more.

Today we’ve discussed the types of hearing organs that various animals have. You should be familiar with animals that have external vibrating membranes, animals that have auditory canals, animals that have auricles, and animals that use echolocation. If you understand these various types of hearing organs, then you understand the important points of this lecture.

13. How is the information in the lecture organized?

A.

Various types of auricles are outlined.

B.

Examples of various hearing mechanisms are provided.

C.

Smaller to larger animals are described.

D.

Various types of hearing organs are evaluated for their effectiveness.

14. Which animal has the disks behind eyes?

A.

Frog

B.

Bird

C.

Cricket

15. Which animal has the membranes on legs?

A.

Frog

B.

Cricket

C.

Bird

16. Which animal has auditory canals?

A.

Frog

B.

Bird

C.

Cricket

17. What do the disks on frogs do?

A.

They reflect sound waves off objects.

B.

They allow heat to escape the body.

C.

They lead to the inner ear.

D.

They vibrate when struck by sound waves.

18. What is true about mammals?

A.

They generally have auricles.

B.

They use echolocation.

C.

They have membranes on their auditory canals.

D.

They hear better than birds.

19. Listen again to part of the passage. Then answer the question. Why does the professor say this?

A.

To reinforce a particularly important point

B.

To summarize previously stated information

C.

To indicate that the lecture is coming to an end

D.

To announce that a slightly different topic will follow

20. What is true about echolocation?

A.

It involves making sounds and then waiting to hear echoes.

B.

It is only used by land animals.

C.

It cannot be used to determine how distant objects are.

D.

It can be used to detect objects in the way.

Script:

Listen to part of a conversation between a student and a university employee.

Employee: Oh, hello . . . can I help you?

Student: Um . . . yeah . . . I′m looking for professor Kirk, is she here? I mean, is this her office?

Employee: Yes, you′re in the right place— professor Kirk′s office is right behind me—but no . . . she′s not here right now.

Student: Um, do you know when she′ll be back?

Employee: Well, she′s teaching all morning. She won′t be back until . . . let me check . . . hmm, she won′t be back until . . . after lunch. That′s when she has her office hours. Perhaps you could come back then?

Student: Oh, unfortunately no. I have class this afternoon. And I was really hoping to talk to her today. Hey, um, do you know if . . . she′s accepting any more students into her introduction to biology class?

Employee: You want to know if you can take the class?

Student: Yes, if she′s letting any more students sign up, I′d like, I′d like to join the class.

Employee: Introduction to biology is a very popular class, especially when she teaches it. A lot of students take it.

Student: Yeah, that′s why the registrar said it was full. I′ve got the form the registrar gave me, um, with me to get her permission to take the class. It′s all filled out except for her signature. I′m hoping she′ll let me in even though the class is full. You, see I′m a senior this year, and uh, . . . this′ll be my last semester, so it′s my last chance . . .

Employee: Oh, wow, really. I mean, most students fulfill their science requirement the first year.

Student: Well, I mean, um...to be honest, I kept putting it off. I′m not really a big fan of science classes in general, and with the labs and everything, I′ve never quite found the time.

Employee: Your advisor didn′t say anything?

Student: Well, to tell you the truth she′s been after me to take a class like this for a while, but I′m double majoring in art and journalism and so my schedule′s been really tight with all the classes I gotta′ take, so somehow I never . . .

Employee: (politely cutting in) Well, perhaps you could leave the form with me and I′ll see if she′ll sign it for you.

Student: You know, I appreciate that, but maybe I should explain the problem to her in person . . . I didn′t want to do it, but I guess I′ll have to send her an e-mail.

Employee: Hmm. You know, not all professors check their e-mails regularly—I . . . I′m not sure if professor Kirk does it or not. Here′s an idea . . . Why don′t you stick a note explaining your situation under her door and ask her to call you if she needs more information?

Student: Hey, that′s a good idea; and then I can leave the form with you—if you still don′t mind. . .

21. Why does the student go to Professor Kirk′s office?

A.

To respond to Professor Kirk's invitation

B.

To ask Professor Kirk to be his advisor

C.

To ask Professor Kirk to sign a form

D.

To find out if he needs to take a certain class to graduate

22. Why is the woman surprised at the man′s request?

A.

A journalism student should not need a biology class.

B.

He has waited until his senior year to take Introduction to Biology.

C.

Professor Kirk no longer teaches Introduction to Biology.

D.

He has not tried to sign up for Introduction to Biology at the registrar's office.

23. What does the man say about his advisor?

A.

She thinks very highly of Professor Kirk.

B.

She is not aware of the man's problem.

C.

She encouraged the man to major in journalism.

D.

She encouraged the man to take a science class.

24. How will the man probably try to communicate his problem to Professor Kirk?

A.

By sending an e-mail to her

B.

By calling her

C.

By leaving her a note

D.

By visiting her during office hours

25. Listen again to part of the conversation. Why does the man say this to the woman?

A.

To thank the woman for solving his problem

B.

To politely refuse the woman's suggestion

C.

To explain why he needs the woman's help

D.

To show that he understands that the woman is busy

Script:

Listen to a discussion by a group of students in an oceanography class.

Instructor: OK, in this course, we′ve discussed a number of the ocean’s unusual features. Today we’re going to discuss atolls and how they′re formed. First, can you tell me what an atoll is? Beth?

Beth: An atoll’s a ring-shaped mass of coral and algae.

Instructor: That’s right. An atoll’s made of coral and algae, and it’s in the shape of a ring. . . . And where’re atolls found? Jim?

Jim: Atolls′re found in tropical and subtropical areas of the ocean.

Instructor: It’s true that atolls’re found in tropical and subtropical areas. . . . Why is that, do you think?

Jim: It’s where the water temperature’s fairly warm. The coral and reef-building algae grow best in fairly warm water.

Instructor: OK, now, let’s look at how atolls’re formed. We’ll look at a series of three diagrams and discuss what′s happening in each. This diagram shows the first step in the process. What does the diagram show? Linda?

Linda: Well, it . . . uh . . . looks like a volcano.

Instructor: (dryly) It certainly does . . . but perhaps there’s something more you could add.

Linda: Uh, it’s a volcanic island ... a newer volcanic island that has formed recently.

Instructor: And what’s growing around the volcanic island?

Linda: Ah ... a coral reefs growing around this new volcanic island.

Instructor: Yes, good. ... OK, now let’s look at the second diagram. Beth, can you describe what’s happening in this diagram?

Beth: The second diagram shows that the volcanic island has started to erode – it’s wearing down.

Instructor: And what’s been happening with the coral reef while the volcanic island has been eroding?

Beth: The coral reef has continued to grow.

Instructor: Excellent. Now let’s look at the third diagram in the series. What’s happening in this diagram? Jim?

Jim: Well, in this diagram, you can see that the volcanic island has, um, worn down so far that it’s below the level of the ocean. The coral has built up even further, so the coral′s above the water, and the remains of the volcano are under water.

Instructor: Yes, and it’s at this stage when the ring of coral’s called an atoll. The volcano has sunk, and there’s a pool of water inside the atoll. Now, what do we call the pool of water that remains inside an atoll? Linda?

Linda: The pool of water inside the atoll is called a lagoon.

Instructor: That’s correct. The body of water inside an atoll is called a lagoon.

Well, you seem to understand quite clearly how atolls result when coral reefs around volcanic islands continue to grow as the volcanic island themselves diminish. That’s all for today. I′ll see you next class.

26. What is this discussion mainly about?

A.

Where atolls most likely occur

B.

The formation of lagoons

C.

How oceanic volcanoes occur

D.

The formation of certain coralline structures

27. What is an atoll made of?

A.

Only of algae

B.

Only of coral

C.

A combination of algae and volcanic ash

D.

A combination of coral and algae

28. Where do atolls tend to grow?

A.

In cool water

B.

In warm water

C.

In tropical areas

D.

In arctic areas

29. Listen again to part of the discussion. Then answer the question. Why does the instructor say this?

A.

She does not understand the student's response.

B.

She would like a more thorough response from the student.

C.

The student's response was incorrect.

D.

The diagram they are looking at is not clear enough.

30. Which occurs in the first step?

A.

The volcano erodes.

B.

The volcano disappears underwater.

C.

A volcanic island forms.

D.

Coral begins to grow.

31. Which occurs in the second step?

A.

The volcano disappears underwater.

B.

Coral begins to grow.

C.

The volcano erodes.

D.

A volcanic island forms.

32. Which occurs in the third step?

A.

Coral begins to grow.

B.

A volcanic island forms.

C.

The volcano disappears underwater.

D.

The volcano erodes.

33. Which occurs in the fourth step?

A.

The volcano disappears underwater.

B.

Coral begins to grow.

C.

The volcano erodes.

D.

A volcanic island forms.

34. What is true about a lagoon?

A.

It is surrounded by an atoll.

B.

It is made of coral.

C.

It encircles an atoll.

D.

It is a body of water.

Script:

Listen to part of a talk in a biology class.

M: Until recently, we knew almost nothing about how important bees are in maintaining natural diversity. Now we know more about them. We know, for example, that honeybees are the dominant pollinators because they play a role in pollinating four out of five food crops in North America. We also know that honeybees along with the other insects, bats, and birds that transfer pollen between flowers—all together they contribute more than ten billion dollars a year to fruit and seed production on North American farms. Pollination is one of nature’s services to farmers. So think about this: if you eliminated the pollinators, it would take the food right out of our mouths. We biologists never imagined we′d see the day when wild plants or crops suffered from pollinator scarcity. But, unfortunately, that day has come. In fact, fanners in Mexico and the U.S. are suffering the worst pollinator crisis in history. So ... what happened? Any ideas? Alicia?

W: Is it ... um ... because of natural enemies? I read something about a kind of parasite that’s killed lots of bees.

M: It’s true. An outbreak of parasitic mites has caused a steep decline in North American populations of honeybees. But parasites aren′t the only factor.

W: What about the pesticides used on farms? All those chemicals must have an effect.

M: Most definitely, yes. Pesticides are a major factor. Both wild and domesticated bees are in serious trouble because of pesticides. In California, farm chemicals are killing around ten percent of all the honeybee colonies. Agriculture in general is part of the problem. Think about this for a minute: the North American continent is a vast collection of “nectar corridors“ made up of flowering plants. These corridors stretch for thousands of miles, from Mexico to as far north as Alaska. And every year, there′s an array of migratory pollinators flying north and south with the seasons, following the flowers. The migratory corridors the flyways—are like ... uh ... something like a path of stepping-stones for the pollinators, with each “stone” being a collection of flowering plants. But our system of large-scale agriculture has interfered. During the past fifty years, millions of acres of desert in western Mexico and the southwestern United States have been turned into chemically intensive farms, planted with exotic grasses, creating huge stretches of fly way that are devoid of nectar-producing plants for migratory pollinators. What we have now are huge gaps between the stepping-stones—patches of plants here and there. A couple of migratory pollinators are worth noting. One is the lesser long nosed bat, and another is the most famous pollinator what is our most famous pollinator? Or I should say our most beautiful pollinator.

W: Oh, I know. It’s the monarch butterfly!

M: The monarch butterfly—yes. Millions of monarchs from all over the U.S. and southern Canada fly south every year in late summer. The monarch is the only butterfly that returns to a specific site year after year. Unfortunately, the herbicides used on the milkweed in the Great Plains are taking a toll on monarchs. and fewer of them are reaching their winter grounds in Mexico. Another important pollinator is the long nosed bat. These amazing animals feed on cactus flowers. What they do is, they lap up the nectar at the bottom of the flower, and then when the bat flics off to another cactus, the pollen stuck to its head is transferred to that plants flower. But the long-nosed bat is having a tough time, too. Some desert ranchers mistake them for vampire bats, and they’ve tried to poison them, or dynamite the caves where they roost.

35. What is the talk mainly about?

A.

Nature's services to farmers

B.

How flowers are pollinated

C.

A decline in pollinator populations

D.

The economic importance of bees

36. According to the professor, what factors have affected pollinator populations? Click on TWO answers.

A.

Hunting

B.

Farm chemicals

C.

Air pollution

D.

Parasites

37. Listen again to part of the talk. Then answer the question. Why does the professor say this?

A.

To describe effects of plant disease

B.

To show the effect of agriculture on pollinators

C.

To describe nectar-producing plants

D.

To show how stones improve a garden

38. Listen again to part of the talk. Then answer the question. What can be inferred about monarch butterflies?

A.

They are the most common butterflies in North America.

B.

Their population has been reduced because of herbicides.

C.

Their diet consists mainly of other butterflies.

D.

They have lived on Earth for several million years.

39. Based on the information in the talk, choose TWO answers that describe long nosed bat.

A.

It has been mistaken for a similar animal.

B.

It returns to the same site every year.

C.

It pollinates four out of five food crops in North America.

D.

It feeds on the nectar of cactus flowers.

40. Based on the information in the talk, choose the answer that describes honey bee.

A.

It pollinates four out of five food crops in North America.

B.

It returns to the same site every year.

C.

It feeds on the nectar of cactus flowers.

D.

It has been mistaken for a similar animal.

41. Based on the information in the talk, choose the answer that describes monarch butterfly.

A.

It pollinates four out of five food crops in North America.

B.

It has been mistaken for a similar animal.

C.

It returns to the same site every year.

D.

It feeds on the nectar of cactus flowers.

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