Exam I9 LV

Complete each sentence with the correct word from the box. 

• attract
• characteristic
• display
• flexible
• evolve
• evidence
• layer
• theory

Match each definition with a vocabulary word. 

What Are Feathers For? 

A Paleontologists think feathers have existed for millions of years. Fossils of a 125-million-year-old dinosaur called a theropod show that it had a thin layer of hair on its back – evidence of very primitive feathers. Discoveries such as this are helping scientists understand how and why feathers evolved.

INSULATION 

B Some paleontologists speculate that feathers began as a kind of insulation. Paleontologists have found theropod fossils with their front limbs spread over their nests. They think this shows that the dinosaurs were using feathers to keep their young warm. In addition, many young birds are covered in light, soft feathers, which keep the birds’ bodies warm. Even when they become adult birds, they keep a layer of warm feathers close to their bodies.

ATTRACTION 

C Another theory is that feathers evolved for display – that is, to be seen. Feathers on birds show a huge range of colors and patterns. In many cases, the purpose of these beautiful feathers is to attract the opposite sex.

D A peacock spreads its brightly colored tail to attract a peahen. Generally, the more eyespots and the bigger the tail, the better the peacock’s chances are of attracting a mate. Other birds use crests – feathers on their heads. In 2009, scientists found evidence that supported this theory. They discovered very small sacs – called melanosomes – inside theropod feathers. Melanosomes give feathers their color. The theropod melanosomes look the same as those in the feathers of modern birds.

FLIGHT 

E We know that feathers help birds to fly. Here’s how they work: A bird’s feathers are not the same shape on each side. They are thin and hard on one side, and long and flexible on the other. To lift themselves into the air, birds turn their wings at a particular angle. This movement allows air to go above and below the wings. The difference in air pressure allows them to fly.

F Paleontologists are now carefully studying the closest theropod relatives of birds. They are looking for clues to when and how feathers were first used for flight. A 150-million-year-old dinosaur called Anchiornis may hold the answer. The size of a chicken, it had black-and-white arm and leg feathers. These feathers were similar to modern bird feathers, except that they were the same shape on both sides. Because of this, Anchiornis probably wasn’t able to fly.

G However, scientists also found a small, movable bone in Anchiornis fossils. This bone allowed it to fold its arms to its sides, keeping its arm feathers off the ground as it walked. Modern birds use a similar bone to pull their wings toward their bodies as they fly upwards. According to scientists, this common characteristic suggests that feathered dinosaurs such as Anchiornis evolved flight by moving their feathered arms up and down as they ran, or by jumping from tree to tree.

H Research therefore shows that feathers probably evolved because they offered several advantages. The evidence suggests that their special design and bright colors helped dinosaurs – and later on, birds – stay warm, attract mates, and finally fly high into the sky.

Review the passage from Unit 9. Then read the statements and write in CAPITAL LETTERS if the statement is TRUE or FALSE. 

A Biomimetics is the study of examples from nature and the application of them to human problems. Lately, biomimetics has been praised as a new science with great potential for creating useful products. However, designing products that imitate nature is nothing new. Five hundred years ago, the genius Leonardo da Vinci studied the anatomy and flight patterns of birds in order to create what he called “flying machines.” His lifelong interest in this topic resulted in sketches and notebook drawings that we can examine today.

B According to Leonardo’s notebooks, one of his earliest memories was of a hawk flying over his bed. Later in life, he wrote about the ability of an eagle to fly high in the sky and of ship’s sails to catch the wind so that they moved along. He wrote: “A bird is an instrument working according to mathematical law, an instrument which is within the capacity of man to reproduce with all its movements.”1 Sofor years, Leonardo closely observed the wing structure of birds and bats and made drawings of how they moved through the air. He believed that if he could figure out how birds flew, then he could design a machine that would fly.

C Leonardo’s notebooks also contain over 500 sketches of flying machines. Some had wings like a bat while others were more like helicopters or parachutes. Based on his study of flying animals, Leonardo came to understand several concepts that even today are essential to aerodynamics, the study of how air flows around solid objects. He knew about lift, drag, and airflow. Unfortunately, his work was mostly abstract and, in fact, he never produced a machine that really flew. After his death in 1519, his notes were lost and he is remembered more for his painting than his attempts to imitate the flight of animals.

Read the passage. Then read each question and choose the correct answer. 

23. What is the main idea of the reading passage?

24. What is NOT in Leonardo da Vinci’s notebooks?

25. What is the best example of biomimetics?

26. What does the quote in Paragraph B suggest?

27. Which of these would be an example of aerodynamics?

28. Why are lift, drag and airflow mentioned in Paragraph C?

29. Which opinion is the author most likely to support?

A Since the time of Aristotle 2,400 years ago, people have been fascinated by how gecko lizards stick to walls as they move around. The famous philosopher noted that geckos easily climbed up and down, facing in either direction. Early observers believed that the little lizards had sticky material on their feet that helped them stay on the wall. Later, lizard-watchers speculated that gecko feet had tiny suction cups. Until recent years, it wasn’t important to actually investigate these theories with experiments.

B Then, scientists thought that if they could learn how lizards climbed, they could imitate geckos in making a strong adhesive, or glue. They hoped to create something that could securely hold a heavy object on a wall, then be removed without leaving a mark. When geckos arrive at the top or bottom of a wall, there is no evidence of their climb. So, at several universities, researchers started experiments to learn more about geckos.

C A physicist named van der Waals theorized that tiny molecules interacted with neighboring molecules. When biologists examined geckos’ feet, they found microscopic hairs called setae on each toepad. Dr. Robert Wall of the University of California, Berkeley, confirmed that van der Waals’ theory explained the geckos’ climbing ability. In 2003, researchers at the University of Manchester developed gecko tape, made from synthetic material that imitates gecko feet. By 2012, scientists at the University of Massachusetts had invented Geckskin, a thin material that can attach up to 700 pounds to a wall. That team’s work was based on the fact that geckos have stiff tendons attached to their toes.

D Inspired by the biology of geckos, researchers around the globe are exploring ways in which gecko adhesion can be used for consumer, scientific, and military purposes. Scientists suggest that there will be many future gecko products.

Quickly skim the reading. Then look at each sentence and find the verb that indicates a theory. Write the verb in the space. 

Write a word from the box that has a similar meaning to the underlined part in each sentence.

• artificial
• lately
• reach
• tiny
• world

40.The following five sentences are NOT in order. Put them in order to form a summary paragraph. Use the list of items below to decide where each sentence belongs. Write the number of the sentence for your answer. 

1. After da Vinci died, many of these notebooks were lost, so today he is remembered mostly for his art.

2. His adult notebooks contain hundreds of drawings of birds, bats, and designs of early airplanes.

3. Da Vinci’s lifelong work was theoretical, so he never made a real flying machine, but it is clear that he understood the concept of biomimetics.

4. Biomimetics is not new because 500 years ago, Leonardo da Vinci studied animal flight to design flying machines.

5. From childhood, he believed that if people understood how birds and bats flew, they could also fly

Read each sentence. Choose the option with the closest meaning to each underlined word. 

41. This field of study is known as biometrics.

42. The other piece has soft loops that allow the hooks to attach to it.

43. Carl worked seven days a week so that he could launch his own business.

44. Recent studies suggest that birds are closely related to dinosaurs.

45. Be careful in that river because the current is very strong and dangerous.

Read the passage below. 

A Since the time of Aristotle 2,400 years ago, people have been fascinated by how gecko lizards stick to walls as they move around. The famous philosopher noted that geckos easily climbed up and down, facing in either direction. Early observers believed that the little lizards had sticky material on their feet that helped them stay on the wall. Later, lizard-watchers speculated that gecko feet had tiny suction cups. Until recent years, it wasn’t important to actually investigate these theories with experiments.

B Then, scientists thought that if they could learn how lizards climbed, they could imitate geckos in making a strong adhesive, or glue. They hoped to create something that could securely hold a heavy object on a wall, then be removed without leaving a mark. When geckos arrive at the top or bottom of a wall, there is no evidence of their climb. So, at several universities, researchers started experiments to learn more about geckos.

C A physicist named van der Waals theorized that tiny molecules interacted with neighboring molecules. When biologists examined geckos’ feet, they found microscopic hairs called setae on each toepad. Dr. Robert Wall of the University of California, Berkeley, confirmed that van der Waals’ theory explained the geckos’ climbing ability. In 2003, researchers at the University of Manchester developed gecko tape, made from synthetic material that imitates gecko feet. By 2012, scientists at the University of Massachusetts had invented Geckskin, a thin material that can attach up to 700 pounds to a wall. That team’s work was based on the fact that geckos have stiff tendons attached to their toes.

D Inspired by the biology of geckos, researchers around the globe are exploring ways in which gecko adhesion can be used for consumer, scientific, and military purposes. Scientists suggest that there will be many future gecko products.

Ideas: 

– For hundreds of years people had theories about how geckos climbed.

– In the last two decades, researchers studied geckos’ feet.

– Scientists have developed gecko tape and Geckskin.

– In the future, there may be more products that imitate geckos.

46. Use the ideas above to write a summary paragraph about gecko research. Organize the ideas and use synonyms in your paragraph. Make sure your paragraph has a topic sentence, two main points, and a closing sentence