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1 Cause and Effect NGSSS LA.7.l.7A: Identify cause-and-effect relationships in a text IIIIIIIIIIIIIIIII Imagine you are eagerly awaiting a concert by your favorite band. At the last minute, you find out the concert has been canceled. Why? A snowstorm has shut down the airports all across the region, and the band members cannot fly in. Why did something happen? That's a question we ask ourselves often. We want to know the reason, or cause, of an event or action. Likewise, we often want to know what will happen as a result, or effect, of an event or action. In the example above, the canceled concert is the effect (what happened), and the snowstorm is the cause (why it happened). When you read, you will also come across cause-and-effect relationships. For example, an article titled "Start Exercising Today" will likely describe the positive effects of getting exercise. Writers often use cause and effect in texts that expla in something or try to persuade the reader. But any kind of text, including stories, can use cause and effect. How do you spot examples of cause and effect? One way is to look for signal words such as because, since, so, therefore, consequently, due to, and as a result. Writers use these words when they clearly state a cause-and-effect relationship. But sometimes the relationship is implied rather than stated. In that case, you must "read between the lines" to infer causes and effects. When thinking about cause and effect, remember that a cause may have more than one effect, and an effect may have more than one cause. Also, cause-andeffect events may occur in a chain. In a cause-and-effect chain, a cause leads to an effect, and that effect becomes the cause of another effect, and so on. Becoming aware of causes and effects will help you understand what you read. The following chart shows a few examples of cause and effect. Cause Effect missed the bus late for school studied for test received a good grade on test read this lesson understand cause-and-effect relationships in a text NGSSS LA.7.l.7.7

2 Read this article about an Arctic animal. Think about the events that are described and why they happen. Little Lemmings 1 The brow n lemming is a furry rodent that looks like a chubby hamster. Although it is small, it plays a big role in the food chain of the Arctic tundra, where it lives. Lemming populations rise and fall in a roughly four-year cycle. When the grasses, mosses, and roots that lemmings eat are abundant, the lemmings reproduce quickly. Each female may have up to eight young ever y five weeks. As the population grows, the lemmings use up the avai lable food sources, and their living area becomes crowded. As a result, thousands of lemmings migrate to a new area. 2 As they migrate, many lemmings starve or drown as they try to swim across rivers and lakes. This, plus being eaten by predators while on the run, leads to a dramatic drop in their population. Ii What effects occur when lemmings have an abundant supply of food? ~ What events concerning lemmings does the article explain? Why lemming populations rise and fall. ~ How does an abundant food supply affect lemming reproduction? Female lemmings have more babies. ~ As the lemming population grows, what happens? The lemmings eat up a ll the available food in the area and then migrate in large numbers to find more food. ANSWER: When lemmings have an abundant food supply, their population grows rapidly. They eat up all the available food in an area and must migrate to find more. What are the causes of the dramatic drop in lemming populations) NGSSS LA.7.l.7.7

3 Read the passage. Use the Think About It to guide your reading. Then answer the question. Use the Hint to help you. Think About It What announcement is made? Why doesn't Gina respond to it? Hint Notice the word because. What is the cause of Gina's situation? Oh, No! 1 Gina strolled down the aisle, scanning the call numbers. When she spotted the book she was looking fo r, Mummies oj Anci ent Egypt, she pulled it fro m the shelr. Opening the large book to a page in the middle, she saw a fasc inating picture of a cat mummy. She immediately sat down on the fl oor and started read ing. 2 Each page she turned to had another intriguing picture that made her want to read more. She sat quietly absorbed in her book for over 30 minutes. Even the voice making an announcement on the loudspeaker did not disturb her. When she fin ally looked up, she noticed that there was no one around. In fac t, almost all of the lights in the li brary had been turned off. "Oh, no! " she thought. 'T he library is closed!" She quickly called her mom on the phone. Gina found herself in the library after it closed because A she had bee n talking to a librarian for over 30 minutes. B she was completely caught up in the book she was reading. C she could not figure out how to use the phone to ca ll her mom. D she wanted to try reading all through the night at the library. CORRECT ANSWER SUPPORTING DETAILS INCORRECT ANSWERS Answer choice B is correct. The text includes details that show Gina was caught up in her book. She was absorbed in her book for over 30 minutes. Because of this, she didn't take notice of the announcement about the lib rary closing. A is not correct because the passage does not mention a librarian. C is not correct because Gina was able to use the phone to call her mom. D is not correct because the story details suggest that what happened was unplanned. NGSSS LA

4 Think About It What are some of the "dos and don'ts" of planning an escape route? What are the reasons for these dos and don'ts? Are the reasons stated or implied? What should you do if someone gets burned? Why? What reason is given for crawling on your hands and knees if you must exit through smoke? Read the passage. Use each Think About It to guide your reading. Fire Safety Tips 1 Install and maintain smoke detectors-smoke detectors warn you of fire in time to let you escape. Install them on each level of your home and outside each slee ping area. Test them once a week, and replace batteries twice a yea r, or when the device chirps to signal a dead battery! 2 Plan and practice your escape-if fire breaks out in your home, you must get out fast. With your family, plan two ways out of every room. Fire escape routes must not include elevators because they might take you right to the fire. Choose a meeting place outside and stay there! Have the whole fa mily practi ce the escape plan twice a yea r. 3 Space heaters need space-keep portable space heaters at least 3 feet (l meter) from paper, curtains, furniture, clothing, bedding, or anything else that can burn. Never leave heaters on when you leave home or go to bed, and keep children and pets well away from th em. 4 Be careful cooking-keep cooking areas clear of combustibles, and don't leave cooking unattended. Keep pot handles turned inward so children won't kn ock or pull them over the edge of the stove. If grease catches fire, carefu lly slide a lid over the pan to smother the fl ames, and then turn off the burner. 5 A match is a tool for adults-in the hands of a child, matches or lighters are extremely dangerous. Store them up high where kids can't reach them. And teach your children from the start that matches and lighters are tools for adults, not toys for kids. If children find matches, they should tell an adult immediately. 6 Cool a burn-if someone gets burned, immediately place the wound in cool water for 10 to 15 minutes to ease the pain. Do not use butter on a burn, since this can keep the skin from cooling and further damage it. If a burn blisters or chars, see a doctor immediately. 7 Stop, drop, and roll-everyone should know this ru le: If your clothes catch fire, don't run! Stop where you are, drop to the ground, and roll over and over to smother the flames. Cover your face with your hands to protect your face and lungs. 8 Crawl low under smoke-if you encounter smoke using your primary exit, use your alternate route instead. If you must exit through smoke, clean air wi ll be several inches off the floor. Therefore, you should get down on your hands and knees, and crawl 10 the nearest safe exit. -ci ~ E ~ 0-0 =.~ oil ">., " 0-0 U ~ u ;; 'u 0 ~ ~ «E 0 "." u " NGSSS LA

5 Hints Reread the second tip. What word signaling cause and effect can you find in this paragraph? Use the Hints to answer the questions below. Circle the correct answers and provide supporting details from the passages. 1 According to the list of Lips, why should an escape route from a fire not include elevators? A They could take you right to the fire. B They often stop working during a fire. e They operate slowly during a fire. D They can only carry one family at a time. Supporting Details: _ Reread the tip "Cool a burn." Look for a phrase that states the reason for placing the wound in cool water. 2 If someone is burned, the reason for placing the wound in cool water fo r 10 to 15 minutes is to A hold in the heat. B ease the pain. e heal a burn blister. D save a trip to the doctor. Supporting Details: _ Reread the last tip. Do you see a word that clearly signals a causeand-effect relationship? Identify the effect (what you should do) and the cause (why you should ] do it). E w "- o c.~ eo.:: >.. g- U 3 According to the list of tips, if you crawl low under smoke to exit a burning building, then you will be able to A see your way out. B breathe clean air near the floor. e avoid gelling burned on your head. D exit the building faster. Supporting Details: With your partner, shar-e and discuss your allswer-s and suppor-tillg details. NGSSS LA

6 II II I Read the article "Spiders: In Pursuit of Prey" before answering Numbers 1 through 6. Spiders: In Pursuit of PrelJ By Harry Gardner Have you seen a spider today? If you have, that's not surprising. Spiders live everywhere, indoors and out. They have adapted to living in deserts, caves, high mountain peaks, and even under water. There are more than 36,000 known species. In natural environments, scientists estimate that the number of spiders per acre can be tens of thousands up to several million. In fact, according to spider experts, you are probably 6 feet from a spider right now! Spiders are the most common predator on earth. They eat mainly insects. Because spiders a re so numerous and widespread, they are very important in controlling insect populations, including pest insects. Many people think that spiders themselves are insects. In fact, they belong to a class of animals called arachnids. Scientists classify spiders this way because they have two main body parts (insects have three) and because they have eight legs (insects have six). Spiders share these features with other arachnids, such as scorpions, ticks, mites, and daddy longlegs. Both arachnids and insects belong to a larger group of animals ca lled arthropods, which have a hard exoskeleton that covers the body. As predators, spiders are fascinating animals. Many of them use an ingenious tool to catch their prey: a web made of silk. All spiders have the ability to produce silk from glands in their abdomen. Using its two hind legs, a spider can "reel out" a fi ne strand of silk as it constructs its web. Some spiders that build webs, such the common yellow-and-black ga rden spider, ca n produce different kinds of silk. They use a strong, stretchy silk to build the basic framework and add a sticky variety that makes it hard for a trapped insect to get away. Spider silk, which is made up of protein, is extremely flexible but stronger than steel! The garden spider weaves an elega nt snare called an orb web. This type of web is basically round, w ith spokes like a bicycle wheel and many strands connecting the spokes. Some orb weavers lie in wait for their prey at the center of the web. Others attach a trap line to the center of the web " '" and then hide nearby, holding onto the line. When.~ o a struggling insect ca uses the line to vibrate, the u spider springs into action. The oil coating on its feet helps it gl ide across the sticky threads of the web. When it reaches its prey, the spider usually bites it, injec ting paralyzing venom, and then wraps it in silk. NGSSS LA

7 IIIII. If the spider is hungry, it starts digesting the prey right away. Since spiders don't have teeth, they must brea k down their food in another way. They actually do this outside their bodies, by spitting digestive juices onto the insect that begin to liquefy it. Then it can suck down part of its meal a little at a time. Other spiders weave different types of webs. Some build triangle webs, which look like a section of an orb web, and wait for their prey at one end corner of the web. Others build small sheet webs between tall blades of grass or branches of shrubs. Directly above this sheet, the spider may spi n a net of nonsticky threads. The net causes a flying insect to lose its balance and fall onto the sheet, where the spider is lurking. Finally, many indoor spiders build tangle webs, or cobwebs, often in the corner of a room. They may look messy, but they are effective in catching prey. As a spider web gets used to catch meals, it becomes damaged and requires repairs. Orb weavers often build a new web every day, a task that can take less than 30 minutes. If the web damage is minor, the spider repairs it, often eating parts of the old web to conserve sil k. About half of all spiders, including the jumping spider and the wolf spider, do not build webs to catch their food. Sometimes called wandering spiders, they find hiding places and wait for passing prey. Unl ike web-builders, these hunters have excellent eyesight. When a wanderer sees an insect nearby, or feels its movement, it rushes out, pounces on its pray, and paralyzes it with a bite. Then it settles down for a nice lunch. Although large spiders such as the black widow are often featured in scary movies, most spiders are small and harmless to humans. They are useful animals and amazing food-catchers with unusual habits that are fascinating to observe. NGSSS LA.7.l.7.7

8 Spiders are very effective in controlling insect populations because A. they can produce silk. B. they are fascinating animals. C. they are numerous and widespread. D. there are more than 36,000 known species. How is a spider able to break down food outside of its body? A. by wrapping its prey in silk B. by paralyzing its prey with venom C. by spitting digestive juices onto the prey D. by chewing small bites and spitting them out., Because spiders have two main body parts and eight legs, they are classi fied as F. insects. G. animals. H. arachnids. I. arthropods. o Yo u have probably seen a spider today because F. spiders live mainly indoors. G. spiders are common in schools. H. spiders are large and easily seen. I. spiders live in many kinds of environments. e According to the article, what allows wandering spiders to catch prey? A. excellent eyesight B. sensing vibrations C. the webs they build D. a strong sense of smell What effect does the net of nonsticky threads above a sheet web have? F. The net traps and holds a flying insect. G. The net gives the spider a place to wait. H. The net keeps other spiders out of the sheet web. I. The net ca uses a flying insect to fall onto the sheet web. Answer Form 2 CD 4 CD o 6 CD Number Correct eo.~ 0- o U NGSSS LA.7.l.7.7