托福听力--biology class

为了帮助大家高效备考托福，为大家带来托福TPO22口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO22口语Task6听力文本： Listen to part of a lecture in a biology class. (female professor) Many animals live underground, in the soil. Not just little animals like worms but also bigger animals like mammals. Living underground has its advantages. It protects animals from above ground predators. However, the underground environment also presents challenges. And animals that live underground have developed physical adaptations to deal with them. One challenge is, well, simply how to move underground through the dirt. Another challenge for the animal is to protect vulnerable parts of its body from the environment that it's moving through.Now, moving through soil is not like moving through air or water, because soil, earth, is thick and dense, so animals that live underground have evolved physical features that help them move through dirt efficiently. For example, the mole, a small, furry mammal, has really wide, super strong front feet with big claws. The mole's feet act like, uh, like shuffles, so it can dig through dirt. The claws cut into the dirt, loosen it up, and once the dirt is loosened up, the broad feet throw the dirt behind the mole as it moves forward. These shuffle-like front feet allow a mole to dig its way through the dirt astonishingly quickly. But even for an animal that can move efficiently through the dirt, living underground can still be problematic, because it’s easy for particles to get caught in sensitive parts of the animal’s body, like for mammals, in their eyes, so underground animals have developed adaptations to prevent this. Again, let’s take the example of the mole. To begin with, moles have tin y eyes and these eyes are covered with a thin skin, a protective membrane that’s actually got hair on it. These hairs protect the mole’s eyes from dirt particles. So as the mole goes digging through the dirt with its head push forward, the dirt particles come into contact with the hairy membrane covering the mole’s tiny eyes. And the particles just slide by. Don’t get caught in the mole’s eyes. So the eyes, the mole’s sensitive parts, are protected. 托福TPO22口语Task6题目： Using the example of the mole, explain two different types of underground adaptation. 托福TPO22口语Task6满分范文： One challenge for underground animals to live underground is to move underground through dense and thick soil. And these animals develop certain adaptations to solve the problem. For example, mole, a small furry mammal has wide and strong front feet with claws so that when it moves forward, the claws dig into the dirt, loosen thesoil and its broad feet will throw the soil behind. In this way it can move through the hard soil very quickly. Another challenge is to protect the vulnerable parts of their body while moving under the soil. Back to the mole, besides the claws, it develops hairy membrane on their tiny eyes. When the dirt and particles come into contacts with the membrane while the mole is moving forward in the dirt, they just slide by rather than get caught in the mole's eyes. In this way the mole manages to protect its sensitive eyes from the soil and particles. (157 words) 以上是给大家整理的托福TPO22口语Task6听力文本+题目+满分范文，希望对你有所帮助!。

tpo69听力文本TPO 69是托福考试的一套听力材料，下面是该听力材料的文本：Passage 1。

Narrator: Now listen to a conversation between astudent and a professor.Student: Professor Johnson, I'm having trouble understanding the reading assignment for next week. Could you clarify it for me?Professor: Of course, what specifically are you having trouble with?Student: Well, I found the language in the text to be quite complex and I couldn't grasp the main idea.Professor: I understand. The reading is indeed challenging. The main idea is to explore the impact ofclimate change on the Arctic region. It discusses the melting ice caps, rising sea levels, and the effect on wildlife.Student: Ah, I see. So, the focus is on how climate change affects the Arctic.Professor: Exactly. It also examines the efforts being made to mitigate the effects and preserve the ecosystem. Make sure to take note of the different strategies mentioned in the text.Student: Thank you, Professor. I will make sure to review the text again with this in mind.Passage 2。

为了帮助大家高效备考托福，为大家带来托福TPO30口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO30口语Task6听力文本： Listen to part of a lecture from a Biology class. When we humans walk from place to place, we move on the Earth's surface, across the Earth's surface. Many animals of course do the same thing. Horses and dogs and cows and so on, all move on the surface, across the surface of the Earth. But there are also quite a few animals that have the ability to move from place to place underground, beneath the Earth's surface. This moving around underground is called subsurface locomotion. Sub surface location has a number of benefits.One benefit of subsurface locomotion is that it enables animals to minimize their exposure to extreme temperatures. This is very helpful to animals that live in areas with harsh climates, where it could be very dangerous to spend large amounts of time on the surface. For example, in the Sahara Desert, in Africa, there's a type of lizard that's able to move beneath the surface, through the sand, very quickly. Because this lizard can move so easily and so quickly underground, it doesn’t have to travel on the surface, where it would be exposed to dangerously high temperatures.Another benefit of subsurface locomotion is that it can help animals capture prey. That’s because animals on the surface can’t see predators approaching underground. Our lizard in the Sahara Desert is again, a good example. The way it works is, when an insect is walking nearby on the surface, it produces very subtle vibrations in the sand. When the lizard senses these vibrations, it moves very quickly. Underground, where it can’t be seen, toward the source of the vibrations. It then pops up directly under the insect and catches it by surprise." 托福TPO30口语Task6题目： Using the example of the lizard form the lecture, explain two benefits of subsurface locomotion. 托福TPO30口语Task6满分范文： One benefit of subsurface locomotion is to allow animals minimize their exposure to extreme temperatures, especially those that could be very dangerous. A good example of this is a kind of lizard that lives in Sahara Desert in Africa. The lizard can move quickly underground to keep from the dangerously high temperature. Another is that it can help the animals catch their preys more easily because the preys above the ground usually fail to see them when they moves beneath. Back to our lizard, it preys on small insects that move above the ground, and the movement produces subtle vibration that can be detected by the lizard. So the lizard moves quickly through the sand toward the source of the vibration, and then pops up from the soil to captureand eat the prey. (135 words) 以上是给大家整理的托福TPO30口语Task6听力文本+题目+满分范文，希望对你有所帮助!。

【必备资料】ETS官方听力托福样题-生物课讲座ETS官方托福听力样题对托福备考阶段的考生具有非常重要的参考价值。

通过样题可以迅速了解ETS的出题风格，和考试类型思路。

那么，在以下内容中，我们就为大家全面带来ETS官方的听力样题，希望这些内容能为大家的托福备考带来帮助。

NarratorListen to part of a lecture in a biology class.ProfessorSo today we’re gonna talk about song development in birds and how—you may besurprised to know—the songs of most songbird species are learned—not completelyinstinctual—which is what we used to think…so I’d like to start things off todayby, um, centering our discussion on the chaffinch.The chaffinch is a type of European songbird, and we’re gonna use thechaffinch’s song development as illustrative of songbirds’ song development ingeneral, because many other songbirds follow this same pattern, this pattern oflearning songs.Okay, so soon after hatching, baby chaffinches start producing these, um,begging sounds, begging calls, actually, which basically are a message to theparents saying, “Feed me; feed me.” That’s all for about the first five weeks,until they grow feathers and start getting ready to fly, you know, become fledglings, and then those calls—those begging sounds—are replaced by, uh, well…you know how babies—human babies—you know how they make that…baby…babbling sound? Like little, soft, vocalized…murmurings? Well, that’s pretty much similar to the noises that fledgling chaffinches make at this next stage of development…which is called subsong…“Subsong” makes sense, right, because “sub” means “below,” and so the subsong is…uh, below, or…happens before their mature song, right? It’s an immature, or underdeveloped song, a baby song. Make sense?Okay, now, they’re not begging for food anymore with the subsong. So what doyou figure they’re making these soft murmurings for? Well, it’s at this stage—what we call early subsong—that, and this is important, the chaffinch’s subsong begins to provide auditory feedback from which the chaffinch learns, and so...self-learning is taking place, because the fledgling hears itself calling out, hears the sounds it’s making, you know, hears, hears its subsong, and so,it’s kinda’ comparing it to the parent’s song and so self-learning is taking place, um, through this process…get it?…Alright. Now, as the chaffinch gets a little older, it enters into what couldbe called late subsong where parts of its subsong start sounding more and morelike its parent’s song,and we have the next step in song development taking place in late subsong,that is, the introduction of plastic song within the subsong--plastic songreferring to—I don’t have to write that on the board, do I?—referring to the parts of the subsong that sound like the parent’s song.Plastic song. Does that sound a little strange to you? Well, keep in mindthat “plastic” has, um, formative implications, you know, it can mean, like, growth, or development into something…like what the chaffinch’s song is doing…it’s developing into its parent’s song…it’s, uh, not quite fully realized yet—it doesn’t sound precisely like its parent’s song—remember this is still the subsong stage we’re talking about—but it’s on its way, the fledgling is still learning, imitating parts of itsparent’s song, just not quite the whole thing yet.So. The fledgling gets older and now it’s winter, and during the winter, the young chaffinch doesn’t practice its singing. But in the spring, the chaffinchstarts back up again, singing and practicing, and this time there is more of an emergence of plastic song, ah…a stronger presence of it within the subsong, and so thereby, the parent’s song is growing increasingly more recognizable and distinct, follow? Then, after about a month, the young chaffinch’s song crystallizes into what’s called full song—the, um, exact song the adults sing. So full song’s, uh, a full-blown imitation of the adult song. Alright?Now what’s interesting is that chaffinches are able to complete this process, even from only a short exposure to their parents’ song. Exposure during thefirst few weeks of life is really all they need, and after that they can remember it, even though they need quite a bit of practice to produce it accurately themselves. So the theory is that there is a sensitive period in the chaffinch’s early life, its early development, a special sensitive period during which it learns what its song should sound like. So chaffinches, um, along with many other birds, learn songs early in life, and when they become adults, they don’t change their songs—it’s a copy of the parents’ song, like we said, okay?NarratorNow get ready to answer the questions. You may use your notes to help you answer.18. What aspect of a chaffinch’s song does the professor mainly discuss? How it is used to beg for foodHow it has changed over several generationsHow its development differs from that of other songbirdsHow it develops from an early age19. What does the professor say about plastic song?It imitates only parts of the parent’s song.It is identical to subsong.It is instinctual and does not need to be learned.It represents the final stage in a chaffinch’s song development.20. What is the evidence for chaffinches’ having a sensitive period for song learning?They begin to practice their song in the spring.They do not develop full song until their second year.They need little exposure to adult song in order to learn it.They do not make many sounds for the first five weeks of their lives.。

为了帮助大家高效备考托福，为大家带来托福TPO15口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO15口语Task6听力文本： Listen to part of a lecture in a biology class. Professor: Birds have some of the best vision capabilities in the animal kingdom. Some bird species have vision that is 8 to 10 times greater than humans. Overall a bird's eyes are extremely important for its survival. One aspect of birds' eyes that plays a role in helping them survive, in other words to find food or to avoid predators, is the position of the eyes in the skull.Some birds have eyes that face forward on the skull, kind of similar to how humans' eyes are positioned. Forward-facing eyes allow a bird to clearly see and judge distances because it can focus on objects with both of its eyes and correctly perceive height, width and depth. One type of bird with eyes positioned in the front of the skull is the hawk. Hawks eat animals like mice. Hawks have such good eyesight that they can spot a tiny mouse in the field from high up in the air. They spot the mouse and swoop down to catch it. Without such good eyesight, they would not be able to spot or catch their food.Other birds have eyes that are located on each side of the skull. This positioning of the eyes can help a bird to avoid predators. Instead of just seeing what's directly in front, they can see things that are on either side, permitting them to watch for danger in all directions. Imagine a duck waiting near the edge of a lake. It needs to spend time eating grasses and insects. But it also is on constant lookout for danger from its predator like the fox. An eye on each side of the duck's head allows it to see a fox approaching from either side. If it spots a fox, it can then fly away to safety. The placement of the eyes are critical in helping the duck avoid predators. 托福TPO15口语Task6题目： Using the examples in the lecture, explain how the position of birds’ eyes is critical to their survival. 托福TPO15口语Task6满分范文： Some birds have eyes that face forwards on the skull, like human eyes. And this kind of eyes allow a bird to clearly see and judge distances with its ability to focus on objects with both eyes and accurately perceive height, width and depth. For example, the hawk has forward eyes on its skull that can allow it to accurately spot its prey, mouse, in the field, even from up in the air. And once it locates the mouse, it swoops down to catch it. Other birds have eyes that are positioned on each side of their skull to help protect themselves from predators. Having eyes on both sides of the skull makes it possible for these birds to watch danger from all directions. For example, a duck eating grasses and insects near the edge of a lake is on constantlookout on both sides for danger from the fox. Once detecting a fox, it can escape. 以上是给大家整理的托福TPO15口语Task6听力文本+题目+满分范文，希望对你有所帮助!。

为了帮助大家高效备考托福，为大家带来托福TPO19口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO19口语Task6听力文本： Listen to part of a lecture in a biology class. (female professor) Today, I want to talk about sea birds. Now, sea birds hunt and eat fish and, well, their food can be hard to find because their food source is spread out over a large expanse of water. So what sea birds have done is that, over time, they've made adaptations: they've developed special characteristics that help them find food.One adaptation involves the length of the bird's wings. Take albatross, for example, is a large sea bird that spends most of its life flying over ocean waters in search of food, fish to feed itself and to carry back to the nest for its chicks. Now, most birds flap their wings up and down when they fly, which uses up a lot of energy, but the albatross has these special long wings that it can hold perfectly still. It's able to fly without moving its wings up and down. These long wings allow it to glide or float on the wind, and this uses very little energy. This is important because as I said the albatross has to cover huge expanse of ocean to locate food, sometimes up to eleven hundred miles a day. Because of its long wings, it can glide along over the ocean using little energy as it searches for food. Another important adaptation of many sea birds is an acute, highly developed sense of smell. Take the fulmar, like the albatross, the fulmar needs to find foods that scatter far out over the ocean, but the fulmar has a rather unusual advantage: it has tiny tubes inside the nose holes in its beak, and these special tube-shaped nostrils help it to pick up scent of food. Now, this highly-developed sense of smell is especially important because the fulmar ’s main source of food, plankton, are tiny organisms that are hard to see, but they give off a very sharp, distinctive odor, so when fulmars are flying around looking for food, they may not be able to see them, but they can find the plankton by smelling them even from far away. 托福TPO19口语Task6题目： Using the examples of the albatross and the fulmar, explain two special adaptations that have developed to help sea birds find food. 托福TPO19口语Task6满分范文： In order to overcome the difficulties locating food in the vast ocean, some sea birds have developed some adaptations. The first one is the length of the wings. For example, the albatross is a sea bird that flies over the ocean waters looking for fish to feed itself and its kids. It has unusually long wings that can help it glide over the sea, so it can save a lot of energy while traveling a large distance for food. The second one is acute sense of smell. For example, fulmar has special tubein its nostril/nose hole to help it pick up the scent of its food, plankton. The plankton is very tiny so the fulmar cannot see it, but it gives out a special odor that fulmar's nose is sensitive to, and thus when the fulmar recognizes the smell of the plankton, it can locate and eat the plankton easily. (147 words） 以上是给大家整理的托福TPO19口语Task6听力文本+题目+满分范文，希望对你有所帮助!。

为了帮助大家高效备考托福，为大家带来托福TPO34口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO34口语Task6听力文本： Listen to part of a lecture in a Biology class. Professor：So, OK, we've been talking about frogs, and like all amphibians, frog has thin skin, which means they lose moisture through their skin easily. Now, typically, we think of frogs as living in wet environments. But for frogs who live in dry places, with desert-like conditions, this can be a problem. Frogs have been able to survive in such areas by havingdifferent physical features, special dry-climate features that help them maintain an adequate level of moisture in their cells and avoid drying out. Some frogs do this by preventing water loss through their skin. By creating a sort of covering over their skin, they greatly reduce their skin's exposure to the dry air. The covering acts like a barrier that locks in moisture. For example, some frogs secrete a substance through their skin, a fatty substance that they rub off over their skin using their hands and feet, which creates a waxy layer all around their bodies that’s almost completely water-tight.Other frogs maintain an adequate level of moisture through a different physical feature, one that allows them to store water inside their bodies for later use. A specially modified internal organ inside their bodies enables them to have a high water-storage capacity. So the frogs are able to absorb and store moisture during wet rainy times which they can rely on to get through dry periods. The aptly named water-holding frog, for example, has a bladder that is highly elastic and stretchable. When it does rain, the frog absorbs water through its skin and its bladder stretches to hold this extra water. The water is then slowly released from the special bladder into the frog’s internal tissues until the next rain which might not be for several months." 托福TPO34口语Task6题目： Using points and examples from the lecture, explain two dry-climate features of frogs. 托福TPO34口语Task6满分范文： There are two ways for frogs to keep moisture in their cells despite their thin skin. The first way is to create certain covering that works as a natural barrier to lock in the moisture to reduce its exposure to the dry air. For example, some frogs would secret a kind of fatty substance through their skin and they rub it off all over their body with hands and feet so that the waxy covering can keep the frog from dehydrating. Another way is a specially modified organ to allow water storage in theirbody for use during dry days. For example, the water-holding frog has a unique bladder that is stretchable. When it rains, it soaks in water and holds it in its body so that the water can then be released into its internal tissues before the next rain, which will probably be quite a while. (147 words) 以上是给大家整理的托福TPO34口语Task6听力文本+题目+满分范文，希望对你有所帮助!。

TPO 14 听力原文Conversation 1Narrator:Listen to a conversation between a student and the librarian employee.Student:Hi, I am looking for this book---the American judicial system. And I can’t seem to findit anywhere. I need to read a chapter for my political science class.Librarian:Let me check in the computer. Um… doesn’t seem to be checked out and it’s not onreserve. You’ve checked the shelves I assume.Student:Yeah, I even checked other shelves and tables next to where the book should be.Librarian:Well, it’s still here in the library. So people must be using it. You know this seems tobe a very popular book tonight. We show six copies. None are checked out. And, yetyou didn’t even find one copy on the shelves. Is it a big class?Student:Maybe about Seventy Five?Librarian:Well, you should ask your professor to put some of the copies on reserve. You knowabout the ‘Reserve system’, right?Student:I know that you have to read reserve books in the library and that you have timelimits. But I didn’t know that I could ask a professor to put a book on the reserve. Imean I thought the professors make that kind of decisions at the beginning of the semester.Librarian:Oh… they can put books on reserve at anytime during the semester.Student:You know reserving book seems a bit unfair. What if someone who is not in the classwants to use the book?Librarian:That’s why I said some copies.Student:Ah, well, I’ll certainly talk to my professor about it tomorrow. But what I am gonna dotonight?Librarian:I guess you could walk around the Poli-Sci ----- ‘Political Science’ section and look atthe books waiting to be re-shelved.Student:There are do seem to be more than normal.Librarian:We are a little short of staff right now. Someone qui t recently, so things aren’t gettingre-shelved as quickly as usual. I don’t think they’ve hired replacement yet, so, yeah,the un-shelved books can get a bit out of hand.Student:This may sound a bit weird. But I’ve been thinking about getting a job. Um… I’venever worked at the library before, But…..Librarian:That’s not a requirement. The job might still be open. At the beginning of the semester we were swamped with applications, but I guess everyone who wants thejob has one by now.Student:What can you tell me about the job?Librarian:Well, we work between six and ten hours a week, so it’s a reasonable amount.Usually we can pick the hours we want to work. But since you’d be starting so late inthe semester, I’m not sure how that would work for you. And… Oh… we get paid thenormal university rates for student employees.Student:So who do I talk to?Librarian:I guess you talk to Dr. Jenkins, the head librarian. She does the hiring.TPO 14 Lecture 1 PsychologyNarrator:Listen to part of a lecture in a psychology classProfessor:We’ve said that the term “Cognition” refers to mental states like: knowing and believing, and to mental processes that we use to arrive at those states. So forexample, reasoning is a cognitive process, so it’s perc eption. We use information thatwe perceive through our senses to help us make decisions to arrive at beliefs and soon. And then there are memory and imagination which relate to the knowledge of things that happen in the past and may happen in the future. So perceiving,remembering, imagining are all internal mental processes that lead to knowing or believing. Yet, each of these processes has limitations, and can lead us to hold mistaken believes or make false predictions. Take memory for example, maybe youhave heard of studies in which people hear a list of related words. Ah…, let`s say a listof different kinds of fruit. After hearing this list, they are presented with several additional words. In this case, we`ll say the additional words were “blanket” and “cheery”. Neither of these words was on the original list, and, well, people will claimcorrectly that “blanket” was not on the original list, they’ll also claim incorrectly thatthe word “cheery” was on the list. Most people are convinced they heard the word “cheery” on the original list. Why do they make such a simple mistake? Well, we think because the words on the list were so closely related, the brain stored only thegist of what they heard. For example, that all the items on the list were types of thefruit. When we tap our memory, our brains often fill in details and quite often thesedetails are actually false. We also see this “fill-in” phenomenon with perception.Perception is the faculty that allows us to process information in the present as we take it via our senses. Again, studies have shown that people will fill in informationthat they thought they perceived even when they didn`t. For example, experimentshave been done where a person hears a sentence, but it is missing the word, that lo gically completes it. They’ll claim to hear that word even though it was never said.So if I were to say…er…the sunrise is in the…and then fill to complete the sentence,people will often claim to have heard the word “east”.In cognitive psychology, we hav e a phrase for this kind of inaccurate “filling in of details”--- it’s called: A Blind Spot. The term originally refers to the place in our eyeswhere the optic nerve connects the back of the eye to the brain. There are no photoreceptors in the area where the nerve connects to the eye. So that particular area ofthe eye is incapable of detecting images. It produces “A Blind Spot” in our field vision.We are unaware of it, because the brain fills in what it thinks belongs in its image, sothe picture always appears complete to us. But the term “blind spot” has also takenon a more general meaning--- it refers to people being unaware of a bias that may affect their judgment about the subject. And the same “blind-spot phenomenon”that affects memory and perception also affects imagination. Imagination is a facultythat some people use to anticipate future events in their lives. But the ease with which we imagine details can lead to unrealistic expectations and can bias our decisions.So…er…Peter, suppose I ask you to image a lunch salad, no problem, right? But I betyou imagine specific ingredients. Did yours have tomatoes, Onion, Lettuce? mine did?Our brains fill in all sorts of details that might not be part of other people’s image of asalad, which could lead to disappointment for us. If the next time we order a salad ina restaurant, we have our imagined salad in mind, that’s not necessarily what we’llget on our plate. The problem is not that we imagine things, but that we assume what we’ve imagined is accu rate. We should be aware that our imagination has thisbuilt-in feature, the blind spot, which makes our predictions fall short of reality.TPO 14 Lecture 2 BiologyNarrator:Listen to part of a lecture in a biology class.Professor:Almost all animals have some way of regulating their body temperature; otherwisethey wouldn’t survive extreme hot or cold conditions---sweating, panting, swimmingto cooler or warmer water; ducking into somewhere cool like a burrow or a hole under a rock; these are just a few. And that’s body is colder or warmer than the surrounding environment, because it’s a microclimate.A microclimate is a group of climate conditions that affect the localized area, weatherfeatures like temperature, wind, moisture and so on. And when I say localized, I mean really localized, because microclimates can be, as the name suggests, pretty small, even less than a square meter. And microclimates are affected by hugenumber of other variables. Obviously weather conditions in the surrounding areas are a factor. But other aspects of the location like, um… the elevation of the land, theplant life nearby, and so on, have a substantial effect on microclimates. And of coursethe human development in the area, eh, a road will affect a nearby microclimate. It’salso interesting to know that microclimates thither or near each other can have verydifferent conditions. In the forest for example, there can be a number of verydifferent microclimates close to each other, because of all the variables I justmentioned.Student:So how does a hole in the ground, a burrow, stay cool in a hot climate?Professor:Well, since cold air sinks, and these spots are shaded, they are usually much coolerthan the surrounding area. And these spots are so important because many animalsrely on microclimates to regulate their body temperature. Hmm, for instance, there isa species of squirrel, in the Western part of the United States that can get really hotwhen they were out foraging for food. So they need a way to cool down. So what’dthey do? They go back to their own burrow. Once they get there, their bodytemperatures decrease very, very quickly. The trip to the burrow prevents thesquirrel from getting too hot.Student:But squirrels are mammals, right? I thought mammals regulate their temperature internally.Professor:Mammals do have the ability to regulate their body temperature, but not all can do itto the same degree, or even the same way. Like when you walk outside on a hot day,you perspire, and your body cools itself down, a classic example of how mammal regulates its own body temperature. But one challenge that squirrels face, well manysmall mammals do, is that because of their size, sweating would make them lose toomuch moisture. They dehydrate. But on the other hand, their small size allows themto fit into very tiny spaces. So for small mammals, microclimates can make a big difference. They rely on microclimates for survival.Student:So cold blood animals, like reptiles, they can’t control their own body temperature,so I can image the effect of microclimate would have on them.Professor:Yes, many reptile insects rely on microclimates to control their body temperature. Alot of reptiles use burrows or stay under rocks to cool down. Of course with reptiles,it’s a balancing act. Staying in the heat for too long can lead to problems, but stayingin the cold can do the same. So reptiles have to be really precise about where they spend their time, even how they position their bodies. And when I say the y’reprecise, I mean it--- some snakes will search out a place under rocks of a specific thickness, because too thin a rock doesn’t keep them cool enough, and too thick a rock will cause them to get too cold. That level of precision is critical to the snake formaintaining its body temperature. And even microscopic organisms rely onmicroclimates for survival.Think about this, decomposing leaves create heat that warms the soil; the warm soilin turn affects the growth, the conditions of organisms there. And those organisms then affect the rate of decomposition of the leaves. So a microclimate can besomething so small and so easily to disturbed that even a tiny change can have a bigimpact. If someone on a hike knocks a couple of rocks over, they could be unwittinglydestroying a microclimate that an animal or organism relies on.TPO 14 Conversation 2Narrator:Listen to a conversation between a student and his faculty adviserAdvisor:Hi ，Steven I schedule this appointment, cause it has been a while since we touch this.Student:I know I have been really busy--- a friend of my works on a school a paper. Heasksme if I would like to try to reporting so I did and I really love it.Advisor:Hey…that's sounds great!Student:Yeah… the first article I wrote it was profile of the chemistry professor---the one whose name teacher the year. My article ran on the front page. When I saw my name, I mean my byline in print, I was hooked. Now I know this is what I want to do--- be a reporter.Advisor:Isn't it great to discover something that you really enjoy? And I read that the articletoo? It was very good.Student:To be honest, the articles got a lot of editing. In fact I barely recognized a couple ofparagraphs. But the editor explained why the changes were made. I learned a lot andmy second article didn't meet nearly many changes.Advisor:Sound like you got a real neck for this.Student:Yeah… anyway, I am glad you schedule this meeting because I want to change mymajor to journalism now.Advisor:Um，the university doesn't offer major in journalism.Student:Oh no…Advisor:But….Student:I… I mean… should I transfer to another school, or major in English?Advisor:Er… wait a minute. Let me explain why the major isn’t offered. Editors at t he newspaper… editors… um… I mean when you apply for a reporting job, editors lookat the two things--- they want to see clips, you know, some of your published articles,though also want to try out, though give you an assignment like… covering a price ofconferences some other event, then see if you can craft the story about it, accurately,on dead line.Student:So they don't even to look at my major?Advisor:It is not that they don't look at it… it is… well, having a degree in something otherthan journalism should actually work to your advantage.Student:How?Advisor:Most journalism specialized these days. They only write about science or business ortechnology for example. Is there a type of reporting you think you may like to specialize then?Student:Well… I think it can be really cool to cover the Supreme Court. I mean… theirdecisionaffects so many people.Advisor:That is really a goal worth striving for. So, why not continue major in political science?And as elective, you could take some Pre-Law classes like Constitution Law, and asfor you work on the student newspaper paper, maybe they let you cover some localcourt cases--- once that the student and professor here would want to read about.Student:Do you know of any？Advisor:I do. Actually, there is case involving this computer software program that one of ourprofessors wrote. The district courts decide in if the university entitle to any of ourprofessors' profits?Student:Wah…. I will definitely follow upon that!TPO 14 Lecture 3 AstronomyNarrator:Listen to part of a lecture in an astronomy class.Professor:OK, last time we talked about ancient agricultural civilizations that observed the starsand then used those observations to keep track of the seasons. But today I want to talk about the importance of stars for early seafarers, about how the fixed patterns of stars were used as navigational aids.OK, you’ve all heard about the Vikings and their impressive navigation skills, but theseafaring people of the pacific islands, the Polynesians and the Micronesians,werequite possibly the world’s greatest navigators. Long before the development of, uh,advanced navigational tools in Europe, pacific islanders were travelling from NewZealand to Hawaii and back again, using nothing but the stars as their navigationalinstruments.Um, the key to the pacific islanders’ success was probably their location near the equator. What that meant was that the sky could be partitioned, divided up, much more symmetrically than it could farther away from the equator. Unlike the Vikings,early observers of the stars in Polynesia or really anywhere along the equator wouldfeel that they were at the very center of things, with the skies to the north and the skies to the south behaving identically, they could see stars going straight up in theeast and straight down in the west. So it was easier to discern the order in the sky than farther north or farther south, where everything would seem more chaotic.Take the case of the Gilbert Islands, they are part of Polynesia, and lie very close tothe equator. And the people there were able to divide the sky into symmetrical boxes,according to the main directions, north, east, south and west. And they couldprecisely describe the location of a star by indicating its position in one of those imaginary boxes. And they realized that you had to know the stars in order tonavigate. In fact there was only one word for both in the Gilbert Islands, when youwanted to the star expert, you ask for a navigator.Um, islanders from all over the pacific learned to use the stars for navigation, and they passed this knowledge down from generation to generation. Some of them utilized stone structures called stone canoes, ah, and these canoes were on land, ofcourse, and you can still see them on some islands today. They were positioned as ifthey were heading in the direction of the points on the sea horizon where certain stars would appear and disappear during the night, and, um, young would-benavigators set by the stones at night and turned in different directions to memorizethe constellations they saw, so they could recognize them and navigate… by them later on when they went out to sea.One important way the Polynesians had for orienting themselves was by using zenithstars. A zenith star was a really bright star that would pass directly overhead atparticular latitude…at a particular distance from the equator, often at a latitude associate with some particular pacific island. So the Polynesians could estimate theirlatitude just by looking straight up, by observing whether a certain zenith star passeddirectly overhead at night, they’d know if they have rates the same latitude as a particular island they were trying to get to. Um, another technique used by the Po lynesians was to look for a star pair, that’s two stars that rise at the same time, orset at the same time, and navigators could use these pairs of stars as reference points,because they rise or set together only at specific latitudes. So navigators might seeone star pair setting together. And, uh…would know how far north or south of the equator they were. And if they kept on going, and the next night they saw the pairsof stars setting separately, then they would know that they were at a different degreeof latitude. So looking at rising and setting star pairs is a good technique. Um…actually it makes more sense with setting stars; they can be watched instead of tryingto guess when they’ll rise.Uh, OK, I think all this shows that navigating doesn’t re ally require fancy navigationalinstruments; the peoples of the pacific islands had such expert knowledge ofastronomy as well as navigation that they were able to navigate over vast stretches ofOpen Ocean. Uh, it's even possible that Polynesian navigators had already sailed tothe Americas, centuries before Columbus.TPO 14 Lecture 4 ArcheologyNarrator:Listen to part of the lecture in the archaeology classProfessor:When we think of large monumental structures built by early societies and Egyptianpyramid probably comes to mind. But there are some even earlier structures in theBritish Isles also worth discussing, and besides the well-known circle of massivestones of Stonehenge which don’t get me wrong is remarkable enough, well, otherimpressive Neolithic structures are found there too. Oh, yes, we are talking about theNeolithic period here, also called new Stone Age, which was the time before stonetools began to be replaced by tools made by bronze and other metals.It was about 5000 years ago, even before the first Egyptian pyramid that some of amazing Neolithic monuments---tombs, were racketed at the very size around ironedGreat Britain and costal islands nearby.I am referring particular to structures that in some cases, look like ordinary naturalhills. But we definitely build by humans, well-organized communities of human’s toenclose a chamber or room within stone walls and sometimes with a high, cleverlydesigned sealing of overlapping stones. These structures are called Passage Graves,because in the chamber, sometime several chambers in fact, could only be entered from the outside through a narrow passage way.Michael:Excuse me, professor, but you said Passage Graves. Was this just monument to honorthe dead buried there or were they designed to be used somehow by the living?Professor:Ah, yes! Good question, Michael. Besides being built as tombs, some of these Passage Graves were definitely what we might call Astronomical Calendars, with chambers they flooded with some light on the certain special days of the year, witchmust see miraculous and inspired good dealer of they really just wonder. Butresearch indicates that not just light but also the physics of sound help to enhance this religious experience.Michael:How so?Professor:Well, first the echoes. When religious leaders started chanting with echoes bouncedoff the stonewalls over and over again, it must seem like a whole chorus of other voices, spirits of God maybe join in. But even more intriguing is what physicistscalledStanding Waves. Basically, the phenomenon of Standing Waves occurs when soundwaves of the same frequency reflect off the walls and meet from opposite directions.So, the volume seems to alternate between very loud and very soft. You can stand quite near a man singing in loud voice and hardly hear him. Yet step little further away and voice is almost defining. As you move around chamber, the volume of thesound goes way up and way down, depending on where you are and these standingwaves. And often the acoustic makes it hard to identify where sounds are coming from. It is powerful voices that are speaking to you or chanting from inside your ownhead. This had to engender powerful sense of all Neolithic worshipers.And another bit of physics I played here is something called Resonance. I know physics, but well I imagine you have all below near of top empty bottles and heardsounds it makes. And you probably notice that depending on its size--- each emptybottle plays one particular music note. Or it is the physics might put it, each bottle resonates at a particular frequency. Well, that’s true of these chambers too. If you make a constant noise inside the chamber, maybe by steadily beating drum at certainrate, a particular frequency of sound will resonate. We will ring out intensely,depending on the size of chamber. In some of large chambers though, theseintensified sound may be too deep for us to hear, we can feel it. We are mysteriouslyagitated by a….but it is not a sound our ears can hear. The psychologic al effects of allthese extraordinary sounds can be profound, especially when they seem sodisconnected from human doing drumming or chanting. And there can be observablephysical effects on people too. In fact, the sounds can cause headaches, feelings ofdizziness, increase heartache, that sort of thing, you see.Anyway, what is we experience inside one of these Passage Graves clearly could befar more intense than everyday reality outside which made them very special places.But back to your question, Michael, as to whether these Graves were designed to beused by the living. Well, certainly, we have got to ask economical or calendarfunction. That seems pretty obvious, and I wanna go into more detail on that now.。

【托福听力备考】TPO12听力文本——Lecture 1众所周知，托福TPO材料是备考托福听力最好的材料。

相信众多备考托福的同学也一直在练习这套材料，那么在以下内容中我们就为大家带来托福TPO听力练习的文本，希望能为大家的备考带来帮助。

TPO12 Lecture 1 BiologyNarrator:Listen to part of a lecture in a Biology Class.ProfessorAs we learn more about the DNA in human cells and how it controls thegrowth and development of cells, then maybe we can explain a very importantobservation, that when we try to grow most human cells in a laboratory, theyseem programmed to divide only a certain number of times before they die.Now this differs with the type of cell. Some cells, like nerve cells, onlydivide seven to nine times in their total life. Others, like skin cells, willdivide many, many more times. But finally the cells stop renewing themselves andthey die. And in the cells of the human body itself, in the cells of everyorgan, of almost every type of tissue in the body, the same thing will happeneventually.OK, you know that all of a person’s genetic information is contained onvery long pieces of DNA called Chromosomes. 46 of them are in the human cells,that’s 23 pairs of these Chromosomes of various lengths and sizes.Now if you’ll look at this rough drawing of one of them, one Chromosomeabout to divide into two. You see that it sort of looks like, well actually it’smuch more complex than this, but it reminds us a couple of springs linkedtogether, two coiled up pieces of DNA. And if you stretch them out you will find they contain certain genes, certain sequences of DNA that help determine how the cells of the body will develop. When researchers look really carefully at the DNA in Chromosomes though, they were amazed, we all were, to find that only afraction of it, maybe 20-30%, converts into meaningful genetic information. It’sincredible; at least it was to me. But if you took away all the DNA that codes for genes, you still have maybe 70% of the DNA left over. That’s the so-called JUNK DNA. Though the word junk is used sort of tongue-in-cheek.The assumption is that even if this DNA doesn’t make up any of the genes, it must serve some other purpose. Anyway, if we examine these ends of these coils of DNA, we will find a sequence of DNA at each end of every humanChromosome, called a telomere.Now a telomere is a highly repetitious and genetically meaningless sequenceof DNA, what we were calling JUNK DNA. But it does have an important purpose; itis sort of like the plastic tip on each end of a shoelace. It may not help you tie your shoe but that little plastic tip keeps the rest of the shoelace, the shoe string from unraveling into weak and useless threads. Well, the telomeres at the ends of Chromosomes seem to do about the same thing--- protect the genes, the genetically functional parts of the Chromosome, from being damaged. Every time the Chromosome divides, every time one cell divides into two. Pieces of theends of the Chromosome, the telomeres, get broken off. So after each division,the telomeres get shorter and one of the things that may happen after a while isthat pieces of the genes themselves get broken off the Chromosomes. So the Chromosome is now losing important genetic information and is no longerfunctional. But as long as the telomeres are a certain length, they keep this from happening. So it seems that, when the, by looking at the length of the telomeres on specific Chromosomes, we can actually predict pretty much how long certain cells can successfully go on dividing.Now, there are some cells that just seem to keep on dividing regardless, which may not always be a good thing if it gets out of control.But when we analyze these cells chemically, we find something veryinteresting, a chemical in them, an enzyme called telomerase. As bits of the telomere break off from the end of the Chromosome, this chemical, thistelomerase can rebuild it, can help reassemble the protective DNA, the telomere that the Chromosome has lost. Someday we may be able to take any cell and keep it alive functioning and reproducing itself essentially forever through the use of telomerase. And in the future we may have virtually immortal nerve cells and immortal skin cells or whatever, because this chemical, telomerase, can keep the telomeres on the ends of Chromosomes from getting any shorter.希望这些对你的托福备考有帮助，预祝大家托福考试能取得理想成绩。

为了帮助大家高效备考托福，为大家带来托福TPO49口语Task6听力文本+题目+满分范文，希望对大家备考有所帮助。

托福TPO49口语Task6听力文本： Narrator: Listen to part of a lecture in a biology class. Professor: So of course many animals live in groups with others of their species. And there are benefits to living together in groups. It can help animals survive. But there are also certain disadvantages. So today we are going to talk about two disadvantages of living in groups for animals. One disadvantage is that animals that live in groups may be more visible to predators. If there's a big group of animals, predators are more likely to spot them than they would an individual animal on its own. So sometimes animals in a group may be more vulnerable to being captured by predators. For instance, Sardines, really small fish, swim in groups, and other larger ocean animals, like some kind of whales, eat them. So while a whale probably wouldn’t notice one Sardine, it would see a group of Sardines very easily and thus be able to capture them for food. Another disadvantage has to do with caring for the young. In a large group, there are a lot of young animals around and it can be difficult for animals to find or identify their own young. And they may end up taking care of other animals to young instead. So their own young may not get the care they need. For example, some bats live in caves. And with one type of bat, millions of them live together in the same cave. And with young bats so crowded together in the cave. It's sometimes hard for a mother bat to find her babies. So when a mother bat returns from finding food to feed her babies, she might end up feeding the babies of another mother bat, meaning her own babies don’t get fed. 托福TPO49口语Task6题目： Using points and examples from the lecture, explain two disadvantages of living in groups for animals. 托福TPO49口语Task6满分范文： The lecture is focusing on two disadvantages of living in a group for animals. One disadvantage is that animals living in groups are more visible and vulnerable to predators. Take sardines as an example. They swim in groups and they are prey for some large animals such as whales. Although it may be hard for a whale to notice one little Sardine, it is able to see a group of them and capture them for food. Another disadvantage is that living in groups set great barriers for animals to identify their own young and thus have them in good care. For example, one type of bats live togetherin the same cave with millions of them. With too much bats in the same cave, a mother bat may find it’s hard to find her own baby and she may end up feeding the babies of another mother bat, leaving her own babies with no food. 以上是给大家整理的托福TPO49口语Task6听力文本+题目+满分范文，希望对你有所帮助!。