Name Lesson 1 Summary Use with pp. 103–105 Lesson 1: How do living things interact? Ways Living Things Interact One Kind of Living Thing Living things in the same environment Helping Another interact with each other in different ways. Different kinds of living things interact This helps them to survive. with each other in different ways. Some living things live in groups. The A barnacle is an animal in the ocean. members of a group help each other. Some barnacles try to stick onto the skin of Sometimes one living thing helps another a whale. Many barnacles can live on one kind of living thing. For example, a large whale. The whale moves through the water. tree can be a home for a small plant. Other The barnacle opens and closes its shell to living things help each other. Insects and catch food in the water. The barnacles do flowers help each other. The insects get food not hurt the whales. The barnacles do not from the plants. The flowers get pollen. help the whales either. But the whales help the barnacles move and get food. Living in Groups Animals that live together may share Helping One Another jobs. Some animals help protect their group Sometimes living things help each other. from other animals that want to hurt them. A special moth helps the yucca plant. The Animals are safer in a group than when moth gives it pollen from another yucca they are alone. plant. The plant helps the moth. It gives it Prairie dogs live in groups. Coyotes and a place to live. It also gives it food for its eagles eat prairie dogs. Coyotes hunt on the young. The moth lays eggs in the yucca ground. Eagles hunt from the air. Prairie plant. dogs take turns to watch the opening of their Some fish also help each other. Some burrows. The prairie dog whistles if it sees small fish eat the things that live on bigger danger. The group hears the whistle. They all fish. The small fish get food from the bigger run and hide until it is safe to come out. fish. The bigger fish get clean and stay healthy. © Pearson Education, Inc. 3 28 Chapter 4, Lesson 1 Summary Quick Study
Name Lesson 1 Checkpoint Use with pp. 103–105 Lesson 1 Checkpoint 1. List three ways in which living things might interact. 2. Give two examples of how living things benefit from living together. 3. How do yucca moths and yucca plants help each other? 4. Draw Conclusions Why do living things interact? © Pearson Education, Inc. 3 Quick Study Chapter 4, Lesson 1 Checkpoint 29
Name Lesson 2 Summary Use with pp. 106–109 Lesson 2: How do living things get energy? Vocabulary producer a living thing that makes its own food consumer a living thing that eats food herbivore a consumer that eats only plants carnivore a consumer that eats only animals omnivore a consumer that eats both plants and animals prey an animal that is hunted by others for food predator a consumer that hunts for food Sources of Energy The energy moves from the cattail to the Green plants make their own food. crayfish to the raccoon. Living things that make their own food are In this food chain, the cattail is a producers. Producers use energy from the producer. The crayfish and the raccoon Sun to make food. Producers also need air are consumers. The crayfish is prey. Prey and soil to make food. is an animal that is hunted by others for Many living things cannot make their food. The prey gives energy to the predator. own food. They must get their energy from A predator is a consumer that hunts for food they eat. They are consumers. food. The raccoon is a predator. A food web is made up of more than one Kinds of Consumers food chain. Energy might transfer from There are three kinds of consumers. one kind of producer to many kinds of Herbivores are consumers that eat consumers. One kind of consumer might be only plants. Cows and grasshoppers are prey for more than one kind of predator. herbivores. Carnivores are consumers A Changing Food Web that hunt other animals for food. Wolves and badgers are carnivores. Omnivores When one part of a food chain or food are consumers that eat both plants and web is lost, the other parts change too. For animals. People and bears are omnivores. example, prairie dogs and cows eat the same grasses. Sometimes ranchers kill the Food Chains prairie dogs so cows can have more food. But the prairie dogs are also prey. Ferrets © Pearson Education, Inc. 3 Food chains and food webs are groups of producers and consumers. Energy in a eat prairie dogs. Reducing the number of food chain moves from one living thing to prairie dogs means ferrets have less food. another. They do not get energy they need. Many die. One food chain starts with a cattail Badgers eat ferrets. When many ferrets plant. The cattail uses energy from the Sun die, the badgers have to look for other food. to make its food. A crayfish eats the cattail. The loss of prairie dogs also hurts other The cattail transfers its energy to the animals. Golden eagles and foxes also eat crayfish. Then a raccoon eats the crayfish. prairie dogs. Now they need to get their The raccoon gets energy from the crayfish. food energy from other animals. 30 Chapter 4, Lesson 2 Summary Quick Study
Name Lesson 2 Checkpoint Use with pp. 106–109 Lesson 2 Checkpoint 1. Trace the transfer of energy through a food chain that includes raccoons, crayfish, cattails, and sunlight. 2. How did reducing the number of prairie dogs affect ferrets? 3. How does the loss of prairie dogs affect eagles and foxes? 4. Draw Conclusions Tell what happens when a food chain is broken. © Pearson Education, Inc. 3 Quick Study Chapter 4, Lesson 2 Checkpoint 31
Name Lesson 3 Summary Use with pp. 110–113 Lesson 3: How do living things compete? Vocabulary competition when two or more living things need the same resource Competing for Resources Different Kinds of Competition A forest is dark and cool. It has a lot of Sometimes, living things compete tall trees. It has only a few small trees. The for space. Loosestrife is a purple plant. tall trees block the sun. The small trees Someone brought it into the United States are in competition with one another for a long time ago. It grows well near rivers. sunlight. Living things are in competition Animals do not eat it, so it keeps growing. when they need the same resource. The tall Now purple loosestrife takes space away trees get most of the sunlight. It is hard for from other plants. It is winning the the small trees to survive. competition for space in many places. Living things compete for light, food, Sometimes animals and people compete water, living space, and other resources. for space. People move to places where Some living things also compete for mates. animals live. They see coyotes in their The winners of these competitions survive. backyards. They find sea gulls on their The losers may not survive. beaches. Living things also compete for oxygen. Predators and Prey Algae are tiny plants. They give food and Members of predator populations may oxygen to fish and other animals. When compete for prey. Predators that are fast there are too many algae at the surface, and strong catch more food. Some birds some of the algae in the water do not get steal prey from other birds. Predators that the light they need. They die. Living things can get more food will survive and have that eat the dead algae use up a lot of young. The young may be fast and strong oxygen in the pond. Fish and frogs compete like their parents. for the oxygen that is left in the pond. Different kinds of predators also compete Sometimes competition follows a cycle. A for prey. Lions and hyenas may want the cycle is a group of events that repeats. same prey. Lions hunt and kill the prey. For example, lemmings are small Hyenas fight the lions. Hyenas try to steal mammals. They eat grass, seeds, and the prey from the lions. roots. The lemming population has a cycle Prey animals also compete with each of change. About every three years their other. Deer that are strong and healthy population grows large. Then the lemmings © Pearson Education, Inc. 3 are more likely to survive. It is easier for use up many of their resources. Now the them to find mates and to get away from lemmings have to compete for what they predators. need. Some lemmings cannot find enough resources to live. Many of them leave. They look for new habitats. Now there are fewer lemmings. There is less competition for food. The grasses grow back. The cycle begins again. The lemming population begins to grow. 32 Chapter 4, Lesson 3 Summary Quick Study
Name Lesson 3 Checkpoint Use with pp. 110–113 Lesson 3 Checkpoint 1. What do living things compete for? 2. Why do living things compete with one another? 3. What kind of living thing usually survives in a competition? 4. Draw Conclusions Explain the pattern of change in the lemming population over time. © Pearson Education, Inc. 3 Quick Study Chapter 4, Lesson 3 Checkpoint 33
Name Lesson 4 Summary Use with pp. 114–119 Lesson 4: How do environments change? Vocabulary decomposer a living thing that breaks down waste and things that have died decay the action of breaking down waste and things that have died Causes of Change Eruptions and fires are examples of events Animals can change the environment. that change environments. The changes often Beavers build dams. Water fills the area. A kill plants. They can destroy animal homes. new wetland habitat grows. Fish, birds, and But the changes may also make new habitats other animals can live there. The dams flood for other plants and animals. places that used to be dry. Animals that lived Patterns of Change on the dry land have to look for new homes. Living things change together. The changes Natural events can also change ecosystems. happen in patterns. Douglas fir and western Hurricanes can change coastlines. They can hemlock are two types of trees. They grow knock down trees and wear away sand. They in the same forests. Their life cycles are can cause floods. Floods kill plants. They wash connected. away birds’ nests. They spread mud all over. Douglas fir trees have cones. Squirrels knock Floods move soil from one place to another. the cones to the ground. Seeds in the cones A drought is another kind of natural event. sprout on the forest floor. They compete for It is very dry during a drought. Little rain falls. light and other resources. A few survive. They Plants cannot get the water they need. So grow into giant trees. Some grow old and die. plants die. It is hard for many animals to find Mushrooms and other decomposers work water during a drought. Some animals die. on the dead trees. A decomposer is a living Other animals have to move to new places. thing that breaks down wastes and things Living Things Return that have died. This is called decay. Trees use In 1980, a huge volcano in Washington materials in the soil to help them grow. Decay called Mt. St. Helens erupted. This changed the gives some of these materials back to the soil. environment. It burned trees and destroyed When trees die, decomposers help them break forests. Mud and rocks covered large areas. down into the soil. In some places, the ash was three feet thick. Seeds from the hemlock cones fall on the Few things lived after the eruption. Then wind decaying Douglas fir logs. The logs hold water blew seeds of grass, flowers, and trees to the better than the ground. The logs contain © Pearson Education, Inc. 3 mountain. Plants began to grow again. things young hemlock seedlings need to grow. Spiders, beetles, and birds went back to Also, now there is sunlight in the forest where live on Mt. St. Helens. Each year, more plants the big trees used to be. The hemlocks grow grew. More animals went back to eat the quickly. They become tall trees. The trees are plants. Now, squirrels, deer, and elk live there. homes for squirrels, owls, and other animals. Fires also change environments. Lightning Carpenter ants come after the trees die. They may hit a tree. The tree burns. The fire then make nests in the tree trunks. The trees fall to burns plants on the forest floor. But the plants the ground. They decay and become part of that do not burn now have more space. Also, the soil. The life cycles of many living things the ash from fires helps plants to grow. are connected. 34 Chapter 4, Lesson 4 Summary Quick Study
Name Lesson 4 Checkpoint Use with pp. 114–119 Lesson 4 Checkpoint 1. What two kinds of things can cause change in the environment? 2. Explain how fire is a change that can improve growing conditions for plants. 3. List natural events that can cause change in an environment. 4. Describe patterns of change involving Douglas fir and western hemlock trees. © Pearson Education, Inc. 3 Quick Study Chapter 4, Lesson 4 Checkpoint 35
Name Lesson 5 Summary Use with pp. 120–123 Lesson 5: What is a healthy environment for people? What People Need Healthful Foods People need food to survive. Food comes People need a variety of foods to be from farms and ranches. People buy it at healthy. Different foods give us all the the store. vitamins, minerals, and other nutrients People also need clean water to drink. our bodies need. They need clean air to breathe. They need People need whole grains, fruits, and shelter. Shelter keeps people safe from vegetables. They also eat nuts, fish, eggs, the weather. It also keeps them at a good dairy foods, and meats. They need a good temperature. amount of water as well. People need a clean environment. Food should be stored carefully. This They must remove waste to keep the keeps it clean and healthful. Fresh fruits environment clean. Garbage and other and vegetables should be washed and wastes go to different places. Some kept cool. Fish, eggs, dairy foods, and communities put garbage in a landfill. meats should be kept cool. Food should be wrapped and cooked soon. Food that is Water stored too long loses nutrients. In some countries, people get water from Cooks must wash their hands before they streams. Most water in the United States touch food. They must wash their knives comes from wells. Water also comes from and other tools too. They should keep cold special lakes called reservoirs. foods cold and hot foods hot. People should eat cooked foods quickly or put them in the Food refrigerator. Our food may come from far away. Fresh food may arrive on airplanes, boats, From Food to Energy and trucks. Other foods may be canned or Your body digests food when you eat it. frozen. Your digestive system breaks down the food so the body can use it. These are the main Shelter parts of the digestive system. Shelter is different in different places. • Mouth Your teeth break the food into People in hot climates need cool places pieces. Your tongue mixes the food with to live. In cold climates, they need warm saliva. Now you can swallow the food. places. People in cities often live in big • Stomach Your muscles mix the food buildings. with juices. The food becomes a sticky Air paste. • Small Intestine More juices break © Pearson Education, Inc. 3 There are less people in open spaces than down the food. The food parts pass in cities. There are not as many cars and through your intestine walls. They go factories. The air is cleaner in open spaces. into your blood. Clean Environment • Large Intestine Water gets into your Everyone can help protect the blood. Some food parts are not digested. environment. A healthy environment helps They form solid waste and leave the people stay healthy. body. 36 Chapter 4, Lesson 5 Summary Quick Study
Name Lesson 5 Checkpoint Use with pp. 120–123 Lesson 5 Checkpoint 1. Name three things people need to survive. 2. How can you be sure of getting all the nutrients you need? 3. Write the steps that show how an apple changes from the time you eat it until the time you can use its energy. © Pearson Education, Inc. 3 Quick Study Chapter 4, Lesson 5 Checkpoint 37