Unit 2 Biolog ical Sciences Eaith is home to many different living things. In this unit, you will learn ways living things are alike and different, You will also learn how different organisms interact. Finally, you will learn what can happen when their environments change. There are seven lessons in this unit: 1 Similarities Between Plants and Animals Plants and animals are living things. So, they have things in common. In this lesson, you will learn what plants and animals need to stay alive. You will also learn how they meet their needs in similar ways. 2 Differences Between Plants and Animals In most cases, you can easily tell a plant from an animal. They differ in several important ways. In this lesson, you will learn how plants and animals use different kines of body structures to meet their needs. 3 Adaptations Plants and animals live in many different places. They have characteristics that help them survive in those places. In this lesson, you will learn why plants and animals that live in one place may look very different from those in another place. 4 inherited Characteristics Many living things look like their parents. This is because parents pass many of their characteristics to their offspring. In this lesson, you will learn what kinds of characteristics a living thing gets from its parents. 5 Ecosystems All of the living and nonliving things in an area make up the parts of an ecosystem. The organisms there play various roles. In this lesson, you will learn about those roles. You will also leam how the parts of an ecosystem interact. 6 Natural and Human Changes to Ecosystems Like all systems, an ‘ecosystem is made of many parts. If one part changes, it can affect the other parts. In this lesson, you will learn about changes that happen nakurally: You will also learn about changes that human activities can cause, 7 Agriculture Many things people use every day come from plants and animals. These plants and animals are aften raised on farms. In this lesson, You will learn how humans use farming to meet their needs. You will also learn how faring affects the environment. ee 10M Cornemal en bx. Donat neThink about the things that live on Earth, Living things can look and act very differently. You know that a maple tree is different from a rabbit. However, like all living things, a maple treo and a rabbit also have similarities. What Is an Organism? Scientists call all living things organiams. Organisms can look very different from one another. However, all organisms have certain characteristics. They all use food for energy. They all can grow. Every kind of living thing can reproduce. Living things Teproduce to make more of their kind, Living things can also respond to their environment. For example, a sunflower can tum to face the sun. A squirrel can go into a burrow to get out of the rain, Needs of Plants and Animals Plants and animals have the same basic needs. They need water, food, air, and a place to live. Like all living things, plants and uals need energy. They use energy to grow, reproduce, and stay. alive. They gel energy from their environment. Plants and animals must live in places that have enough water, food, and air to meet their needs. All plants and animals need water Plants and animals need water te survive. They need water to help move materials inside their bodies. Most animals take in water through their mouths. Most plants take in water through their roots, All plants and animals also need food. Food is anything that gives an organism energy. Plants and animals need energy to carry ut their functions. For example, animals need energy to breathe and move. Plants need energy to grow and make seeds, Plants and animals cannot stay alive without energy from food. However, they must break down food inte tiny pieces before they can get energy: Similarities Between Plants and Animals Anchor and Eligible Content $4.8.1.1.1-5 Organism is another word for living thing. When organisms reproduce, they make offspring that are like ‘themselves, Plants and animals are not the only kinds of living things. Mushrooms are living things called fungi. Germs are livin things called bacteria, Organisms get energy from food.from it. In animals, the process of breaking down food is called digestion. Plants and animals need oxygen to live. They also need to get rid of gases their bodies produce that they de not need. They have special structures to help them do this. Plants have tiny holes in their leaves through which gases move in and out. Animals have lungs or gills to take in and get rid of gases, This process is called respiration. Which of these is the source of energy for a living thing? A oxygen B air C food D weier All living things need air and water However, oxygen, air, and ‘water are not the source of energy for an organism. So choices A, Band D are incorrect, Living things get energy from food. The correct choice is C. Structure and Function in Plants and Animals Each plant and animal is a system, Like all systems, plants and animals are made up of different structures, or parts. An organism’ body structures carry out different functions for the organist. A structure's function is the job it does. An organisms structures ‘work together to help the organism get the things it needs. Plants have structures called roots, stems, and leaves. Roots help plants take in water. Stems provide support for plants. Leaves help plants take in gases and collect sunlight. Plants use waler, air, and sunlight to make food in their leaves. Animals have structures that help them move. Animals need to move to find food and water. Some animals have wings for flying or fins for swimming, Many animals have legs for walking, running, or hopping over land. Plants and animals need to protect themselves from heat and cold. They also need to protect themselves from organisms that want to eat them. Both plants and animals have body coverings for protection. Many trees have a hard covering called bark. Bark protects trees from damage. It protects them from lasing too much water. A cactus has thin, sharp leaves that cover its body. The sharp leaves help keep animals from eating i. Animals have many different coverings on their bodies. Birds have feathers to keep them warm and Lelp them fly. Fish and UNIT 2 disicaical Sciences © fhe Commer ess, ont ete, 2 Animals break down food inte nutrients in a process called digestion. Respiration is the exchange of gases between organisms and their environments. Plants do not get oxygen only from the air. They also produce oxygen from processes inside their bodies. An organism's structures are the parts that make up the organism's body. The function of a structure is the job that it performs. You can learn more about systems in Unit 1, Lesson 5. The roots of many plants also help to keep the plants in the ground. The roots grow under the soil and help hold the plants in place. A body covering is the material on the outside helps protect the organism.reptiles have hard scales to protect their skin. Many animals have furto keep them warm. A porcupine is covered in sharp spines. ‘The spines protect the porcupine from other animals. Both plants and animals have body parts for protection. All living things grow during some patt of their lives. The way plants and animals grow is part of their life cycle. A life eyele is a pattern of changes that happens during an organism's life. When an ‘organism reproduces, the life cycle repeats. All plants and animals have life eycles. For example, a bean plant grows from a seed toa seedling to an adult. As it grows, it develops roots, stems, and leaves. A grasshopper grows from an egg toa nymph to an adult. As it grows, it gets bigger and develops legs, wings, and other body parts, yee ae ‘Older’ aympet syrah All plants and animals have life cyeles. Deserts get very little rain. Many plants that live in the desert have long roots that spread out under the soil A Identity a need of living things that would be hard for plants and animals to meet in a desert. B How can the roots of some desert plants help them meet their needs? First read the whole question to see if you can find any information, The question tells you that the desert doesn't get ‘much rain. So it’s probably hard for plants and animals to find -water in the desert. For part B, you should think about how long YOOtS Would help a plant get water in a very dry place. Long roots that spread out can help desert plants find and take in the small amounts of water in the soil. (©The Camwaal Pre nc. Do ne ce Some animals, such as | turtles and hermit crabs, | have shells as body | coverings. Hard shells | protect the animals’ soft | bodies. When they are in | danger, many turtles and | hermit crabs can pull | their whole bodi | their shells. | A pattern of changes that happen during an organism's life is the organism's life cycle. Life cycles are patterns because they follow a | certain order and repeat | over time. For example, after a grasshopper | becomes an adult, it lays | eggs. The eggs grow into nymphs that become | adults. Eventually, these | adults lay eggs and theIf's Your Turn Please read each question carefully. To answer each multiple-choice question, circle the comect response. 1 A fish has special structures called gills that let it take oxygen from water instead of air. Which process do gills help a fish carry out? A. gtowth B respiration Cs reproduction D digestion Use the pictures below to answer questions 2 and 3. a. & 2 What do these living things have in common? A. They both have roots, B_ They both move to find food. © They both have body coverings. D_ They both take in air through leaves. 3 What would most likely happen if the tree did not have roots? A. Itwould have toa much oxygen. B It would not get enough air © Itwould have too much food D_ Itwould net get enough water. UNIT:4 Which of these statements true? ‘A Animals need food, but plants do not B Plants need water, but animals do not. © Animals and plants both need carlson dioxide. D Plants and animals both need gases from air. This is a short open-ended question. Write your answers on the lines, 5 A student is observing different kinds of seeds in a forest. He sees an acorn that has begun to sprout. He is interested in how the acorn grows during the rest of its life cycle. He makes a drawing of the acorn below. af | A Describe how the acorn will change in the next stage of its life cyde. B Describe how these changes help the plant meet its needs throughout its life cycle. eee © Whe (tine Pos Ine Do upc‘Anchor and Eligible Content 54.8.1 Plants and animals have many similar needs, but they meet these needs in different ways. They have different kinds of body structures that help them meet their needs. Characteristics of Plants Unlike animals, plants cannot move from place to place. They must get all the things they need in the places they grow. A plant has structures that help it take in what it needs from the environment. ‘Most plants have roots, stams, and leaves, A pea plant stem: holds the plant up. is roots spread out under the soil to take in water The water moves up the stems to the leaves, The leaves have tiny holes that take in air The leaves also soak up sunlight. Plants can make their own food. They use the energy in sunlight to make food from water and carbon dioxide. Most plants make food in their leaves. The food moves through the plant’s body from the leaves to the stem and roots. Like animals, plants use oxygen to get energy from their food. Plants can get oxygen from the air through the holes in their leaves. However, they also produce some oxygen when they make food. Like all living things, plants grow and change during their lives. Most plants grow from seeds. Under the right conditions, a young plant called a seedling will sprout from a seed. Then the seedling ‘can grow into an adult plant at ‘ge Corcnetl Pres ke Do it ales Differences Between Plants and Animals 14 i { | When scientists put organisms into different groups, they classify them, To do this, they use 2 classification system. Plants and animals are two main groups in the system. Each of these groups is made of many smaller ‘groups. For example, ladybugs are in the insect group within the animal group. The roots of a plant are a system, The root system is made up of many small roots that connect to larger roots. “These roots wark together to take in water for the plant. A seedling is @ young plant that grows out from a seed.A stem holds a plant up. Some stems are hard and ‘woody. Some stems are soft and fleshy. A Give an example of a plant with a woody stem and an example of a plant with a fleshy stem. B Explain why most tall plants, such as trees, have woody stems. ‘There are many possible correct answers to part A, but youneed @ to choose only two plants. So, think of plants with woody stems, trees and bushes. A pine tree is a plant with a woody stem. ‘Think of plants with soft stems, like grasses and flowers. A tomato plant isa plant with a fleshy stem. For part B, you need to apply the information in the question and what you already know about plants. A woody stem would give a plant mare support than a fleshy one. Tall plants, such as trees, need more support to hold them up than short plants do. The eastern hemlock is Pennsylvania's state tree, Ithas a woody stem. Characteristics of Animals All animals can move from place to place at some point in their lives. They move around to find what they need to survive. Many animals that live on land, such as deer and birds, move using legs or wings. Other land animals, such as snakes, move by crawlingon their bellies. Some animals that live in water swim using fins, Unlike plants, animals cannot make their own food. They must eat other organisms. After an animal eals, it digests its food. That is, its body breaks down the food into substances that the body can use. Most animals have special structures that help them digest food. Your stomach and intestines help your body digest food, | Like plants, animals need structures to support their bodies ; However, animals do not have stems. Instead, many animals have ‘tons. A skeleton supports an animal’s body and gives it shape. | Asskeleton is a hard | structure that supports | | Insects, such as fireflies, ane some other anitnals have their skeletons on the outside of their bodies. This hard outer covering protects a firefly’s soft body. As the firefly grows, it needs a new: skeleton, It sheds its old skeleton and grows a new one. Spiders and crabs also have skeletons on the outside of their bodies, an animal's body and gives it shape. The firefly is Pennsylvania's state insect. eo. (Dba Certmentl Ps. Ob nt cipleMany animals, such as people, cals, birds, and fish, have skeletons inside their bodies. Most of these animals have skeletons made of bones. The animals do not need new skeletons as they grow. Their bones grow as the animals get bigger. Animals with skeletons on the inside do not shed their skeletons as they grow. When they breathe, animals take in oxygen and release carbon dioxide. Animals use oxygen to get energy from food. In the process, they make carbon dioxide waste. Animals cannot use carbon dioxide like plants do. They get rid af carbon dioxide before it harms their bodies, Most land animals use lungs lor respiration. Lungs help an animal take in air, People, wolves, reptiles, and birds have lungs. Most animals that live in water have gills. Gills help animals take in oxygen from water. A few animals can take in and release gases thiough their skin. Which animal structure has a function most si function of tiny holes in leaves? to the A lungs B skeleton © stomach D wings First think of the funietion of the tiny holes in leaves. The holes take in air, Look for an answer choice that has a similar function in animals. A skeleton does not take in air, so choice Bis incorrect. A stomach helps an animal digest food, so chaice Cis incorrect, Wings help an animal move, so choice Dis incorrect. ‘Many animals use lungs to take in air, so the correct choice is A. ©The Conner Fes Dao epee | Breathing is another word for respiration. Lungs are structures that help animals get oxygen from ait. Gills are structures that let an animal get oxygen from water. oe eee rai eeIs Your Turn ae Please read cach question carefully. To answer cach multiple-choice question, circle the correct response. 1 Seahorses are creatures that live in saltwater sea grass beds and coral reefs. What structure does this seahorse most likely use during respiration? A. stomach lungs B leaves D ills 2 How do leaves help plants make food? A. They take in water, B They develop seeds. They soak up sunlight D- They release carbon dioxide. is baby deer will grow a lot during its first year of life. What Il most likely happen to its skeleton as it grows? It will fall off. tt-will get bigger. twill take in air, A B € D it will break down, The Cantera i Inc Do aaaAdapiations Anchor and Eligible Content $4.8.2.1.1, 2 Different environments are homes to different kinds of -organisins. An environment is everything that is around an ‘An environment is the organism. It includes living things, such as plants and animals,and | _ total of all the things. nonliving things, such as rocks and water. A feature of an organism —_|_‘that surround an that helps it live in its environment is called an adaptation. Some ) oe adaptations are part of a plant's or animals body. Others are behaviors, ar ways a plant or animal acts. Plants and animals in Sree on & : | characteristic of an different environments need different adaptations to help them | organism that helps it purine? | survive in its | environment. Adaptations for Living in Water Swamps and marshes are examples of wetlands. The soil in a wetland is covered by water for most or all of the year. Most animals that live in wetlands have adaptations that help them swim of get things from the water that they need to survive. Frogs are common animals in wetlands. Young frogs are called tadpoles. Like many animals that live in water, tadpoles have gills. Gills are organs that let an animal get oxygen from water, Beavers do not have gills, but they have other adaptations for living in a wetland. A beaver has webbed back feet and a large, flat tail. The webbed feet help the beaver paddle through the water. Its flat tail helps it steer. A beaver can close its nositils and ears when it swims so that water does not get into them A beaver's body has adaptations that help it live in 3 wetland. Like animals that live in wetlanels, animals that live in lakes, rivers, and oceans have adaptations that help them survive in water. The state fish of Pennsylvania is the brook trout. Like a tadpole, a brook trout uses gills to take oxygen from water. A brook trout’ tail and fins help it move. Ils smooth scales help it slide easily through water —UNIT2 (OMe Cowal es, re De at diatePlants that live in water need sunlight to make food, just like all plants do. Mast water plants, stich as cattails, live on the surface of water or in shallow water so that they can get enough sunli Organisms that live in salty ocean water have adaptati Some plants have structures that get rid of extra salt from inside the plant. Animals that live on land cannot survive if they drink salt water. However, many animals that live in oceans, such as fish, have only salt water to drink, These animals have structures that let them send extra salt out of their bodies. Adaptations for Living in Deserts Very little rain falls in desert environments. Mast deserts are hol. You might think of deserts as harsh places to live. However, some ‘omganisms, such as the jackrabbit and the saguaro cactus, are adapted to live in deserts, All of the organisms that live in the desert have adapted to hot, dry conditions. A saguaro cactus is a large desert plant that can store water in its thick stem, The needles that cover a saguaro are actually its leaves. Like the saguaro, most plants that live in deserts have very small or narrow leaves, Small leaves lase less water than large leaves do, The size of the plants leaves is an adaptation that helps the plant survive in a dry environment, Desert animals have adaptations that help them stay cool and keep from losing water, Most small animals that live in deserts, such as jackrabbils, stay underground or hide in shade during the day. ‘This behavior is an adaptation that helps the small animals stay cool when temperatures are very high. A jackrabbit's large ears also help it stay cool, Blood flowing through the rabbit's ears releases extra heat to the ait, ©The Comin ae, nc Den ae 2S Most plants use their Feaves to make food. However, because @ cactus has such tiny leaves, it uses its thick stem to make food.SS =a ‘A jackrabbit has adaptations for living in the desert. Which of these adaptations would best help an animal survive in the desert? A hunting in water C having a thick fur coat B sitting in the sun D getting water from food Most deserts are dry and hot, So, desert animals need adaptations A kangaroo tat can go that help them stay cool and conserve water Thick fur and sitting _its entire life without in the sun do not help an animal stay cool. There is very little drinking water. It gets all water in the desert, so an animal that hunts in the water cannot the water it needs from find food in the desert. Being able to get water from the food it the seets fresh eats can help an animal live in the desert. The correct choice is D. Adaptations for Living in the Tundra A jackrabbit is adapted to live in the desert. In the same way, an arctic hare is adapted to live in its environment, the tundra, | ‘An arctic hare looks different from a jackrabbit. . Little snow or rain falls “The tundra ig avery cold environment found in the far north. it | inthe tundra. When isso cold that the ground is frozen for most of the year. Conditions | snow does fall, the low in the tundra can be harsh, but many animals are well adapted for | ‘temperatures keep it survival there, For example, an arctic fox has thick fur to keep it from melting for most of ‘warm. A seal has a thick layer of fat under its skin that helps it stay | ‘the year. warm in iey waters. Bau The Comin Pr ne De to phateMany tundra aninvals migrate to avoid the coldest parts of the ‘year. During winter on the tundra, there is litte food. Birds that ean live on the tundra int summer must migrate during the winter. They fly south to. warmer places where they can find food. Some tundra animals, such as the arctic ground squirrel and the grizzly bear, hibernate in winter. Hibernation looks much like sleep, but they are not the same thing. When an animal hibernates, its heart beats more slowly, and it breathes more slowly. This helps its body use less energy. The animal does not need to eat or drink. Hibernation lets these animals survive in the calelest months when there is little food. ‘Trees do nat grow in the tundra, The plants that do grow there are all low to the ground. This characteristic keeps the plants out of strong winds and helps them trap warm air near the ground, Adapiations for Living in Grasslands More rain falls in grasslands than in deserts. However, grasslands are still dry places. Beeause grasslands are dry, fires burn easily there. Grasslands in North America are called prairies. Some plants that live on prairies have adaptations that help them survive fires. Prairie grasses have parts of their stems below ground. This is an adaptation for surviving fires, When a fire burns through the prairie, all the plants can bur down to the ground. However, the stems below ground keep the grass alive. After the fire, the grass can start to grow again, Adaptations for Living in Forests Plants that live in forests have adaptations that help them get sunlight or survive with litle sunlight. Oak trees need more sunlight than some other plants, Growing very tall isan adaptation that helps an oak tree hold its eaves above those of other plants. Some plants, such as mountain laurel, can grow in shady areas. Being able to grow in shade is an adaptation. It helps mountain laurels survive in forests in. which many other plants block sunlight. Many animals that live in forests have adaptations that help them blend in with leaves, twigs, or tree bark. Blending in can help an animal hide from predators. Blending in can also help a predator sneak up on its prey. Predators have a hard time seeing this walking stick insect. Looking like a stick is an adaptation that helps these inseets survive. ‘Orbe Cement ess. eo not phe When an animal migrates, it travels long distances during certain seasons. When an animal hibernates, its body functions slow down, and the animal uses less ‘energy. Grassland plants are not the only plants adapted to fire. The seeds of some forest trees can start to grow only after a forest fire, A predator hunts and eats another organism. The organism a predator eats is its prey. — UNIT 2 Biological SciencesOther animals have adaptations to help them stand out rather than blend in. In many cases, bright colors and patterns are warnings that an animal is dangerous. It may be poisonous or venomous. Some animals have bright colors and patterns even though they are not poisonous or venomous. Predators think these animals are dangerous and avoid them. Bright colors and patterns are adaptations that help keep predators away. Eastern coval snake Scarlet king snake These two snakes have similar bright color patterns. ‘The coral snake is venomous. The king snake is not. Monarch butterflies and viceroy butterflies have similar color patterns. Monarch butterflies are poisonous to predators. Viceroy butterflies are not. Monarch A Explain how being poisonous is an adaptation for a monarch butterfly. B Explain how the viceroy butterfly’s color patterns could be an adaptation. An adaptation helps an organism survive. Predators will not want to eat something that is poisonous. Because the two butterflies look similar, predators avoid both the monareh and the viceroy. Looking like a monarch is an adaptation that helps a viceroy butterfly survive. es lire, me. Do nats a 2 Tiny poison-arrow frogs live in Central and South America, These brightly colored frogs are very poisonous. A small amount of poison from ‘one frog's skin can kill a much larger animal A poisonous organism hhas poisons on or in its body that can harm an animal that eats or to eat it, ‘A venomous organism injects its poison into another organism. Blending in is not just a forest adaptation. Almost every environment has some organisms that avoid predators or sneak up on prey by blending into the environment.It's Your Turn Please read each question carefully. To answer each multiplechoice question, circle the correct response, 1 Which of these adaptations would most likely help an animal survive in a place that is cold and dry? A gills thin skin B thick fur 1D large ears 2 Poison-arrow frogs have very bright colors. The skin of a poison-arrow frog contains deadly poisons. Which statement best explains how the adaptation of brightly colored skin is helpful to the frog? A. Ithelps the frag blend in with the environment, tt makes the frog look like a harmless animal Itlets the frog sneak up on prey. gn@ Itwarns predators not to eat the frog. 2 Asscientist is studying an animal. The animal is dark green and can sit very still for a long time. For which environment is this animal most likely adapted? A. desert ocean B forest D tundra Use the picture below to answer question 4. 4 Asscientist is studying the plant shown in the picture above. What can you conclude about the environment this plant lives in? A. tis hot and dry © ttiswarm and rainy. B Ibis cold and windy. Dit is cold and dry ok UNIT 2 Bioiogical sciences te Conental Rew be bose lcsMost living things look and act a lot like their parents. In other words, they have similar characteristics, or features. For example, puppies look and act a lot like adult dogs. Some characteristics are part of an organism's body. They make up how the organism looks. These are called physical characteristics. Other characteristics are not part of an organisms body, They make up the way the organism acts. Inherited Characteristics Inherited characteristics are characteristics that parents pass to their offspring. They are characteristics that a living thing is bern with. I the environment changes, most inherited characteristics do not change. ‘An individual is a single living thing, Most individuals look like their parents. This is because individuals inherit many characteristics from their parents. For example, a girl may have blue eyes like her mother. Most tall people have tall parents. A puppy has four feet, like its parents do. Eye color, height, and number of feet are inherited characteristics. When puppies are born, they look like their parents. Plants also inherit characteristics from their parents. For example, most plants have the same shape of leaves as their parents. The shape of a plant’ leaves is an example of an inherited characteristic. Individuals can also inherit behaviors from their parents. An inherited behavior is called an instinct. Instincts are behaviors that organisms are born knowing how to do. For example, many birds build nests. They do not have to learn how to build nests. “They are born knowing how to do it. Nest building is an instinct, The Conenal Fa Ine Do ciate Inherited Characteristics ‘Anchor and Eligible Content $4.8.22.1 Parents pass on inherited characteristics to their offspring. An individual is a single iving thing. You cannot see all | inherited characteristics ily. Some inherited characteristics affect how ‘an organism leoks. on | the inside. 1 ‘An instinct is a behavior ‘that an organism can do ‘without being taught.Instincts help individuals survive. For example, dueklings have an instinct to stay near their mother after they hatch. Young ducklings are saler near their mother Their instinets help them stay safe. ® The instinct for ducklings to follow their mother strong, If their mother is not close by, they may follow any moving thing they see. This instinct is an adaptation. You ean learn more about adaptations in Unit 2, Lesson 3. Ducklings do not need to learn to follow their mother. Following their mother is an instinct. This instinct helps the ducklings stay safe. Why does a young giraffe have a long neck? Many multiple-choice A It-gtew-a long neck fram stretching, questions have choices B It inherited instincts from its mother. that are true statements but do not answer the € It learned to have a lang neck to get more food question. Be sure to read all the choices before D Itinherited physical characteristics from its parents. ‘Along neck is not a behavior so it cannot be an instinet, Choice B sinconect.A giraffe is born with a long neck. It dées one from stretching, It does not learn how to have a long neck : Choice A and choice C are incorrect. Along neck is an inherited physical characte The correct choice is. Other Characteristics Some characteristics are not inherited. An individual is not born with them, Instead, the organisii gels these characteristics These characte change as the environment Some nonsinherited characteristics affect part of an organism's body. For example, a person may have a sear, pierced ears, or short hair A child does not inherit any of these characteristics from his parents. A child will nat be bor with the same sears or haireut as his parents. The picture on the next page shows another example of a characteristic that is not inherited ‘Guhe Centred Ps eo nt plete.The damage on this leat is one of this plant's characteristics, However, the plant did not inherit the characteristic from its parents. It will not pass it on to its offspring. A student's parents are both tall and have dark brown eyes. Her mother has long fingernails that are painted red, Het father has short hair and likes te sing. ‘A Name two inherited characte probably has. that the person B Name two characteristics the person may have that she did not inherit from her parents. ® ‘The parents can pass only inherited characteristics to their child, Many open-ended ‘The girl is probably fall and has dark brown eyes. She may have questions can have more long fingemails or short hair, but she did not inherit these than one correct answer. characteristics from her parents. You do not need to include every possible : answer. Make sure you read the question carefully so you know | how much you need to write in your answer. i Siicaaacacraamacir _ UNIT 2 Biological SciencesI's Your Turn Please read each question carefully, To answer each multiple choice question, circle the correct response, 1 Which of the following is an example of an inherited physical characteristic? A. Acchild reads a book. € A dog has a collar. BA robin lays blue eggs. D> Aman has short hair, Use the picture below to answer question 2. 2 Which of this girl's characteristics do her parents least likely have? A haircut € skin color B_ eye color D_ face shape Use the paragraph below to answer questions 3 and 4. PLANT CHARACTERISTICS Different kinds of plants have different characteristics. Some plants, such a5 pine trees and oak trees, have hard stems. Other plants, such as grasses and sunflowers, have soft stems. Pine trees have sharp, needle- like leaves. Oak trees, grasses, and sunflowers have soft, green leaves. 3 Which of these characteristics would the offspring of a pine tree most likely have? A. hard stem, soft green leaves hard stem, needle-like leaves B soft stem, neediedike leaves D soft stem, soft green leaves 4 What kind of characteristics does the paragraph describe? A inherited behaviors C_ noninherited behaviors B inherited physical characteristics D_nonsinherited physical characteristics “UNIT 2 Biological sciences (©'e Comins Pres ne Dai uiEcosystems ‘Anchor and Eligible Content 54.8.3.1.1, 2 Farth isa large system made up of many smaller systems. Some Gi ofthesystems that make up Earth are ecosystems. An ecosystem | An ecosystem fs 2 the feallthe ving and nonliving things in an area.As in allsystems, | Tving a0 nonliving gach part of an ecosystem plays a role, Wetlands, forests, ponds, | things that interact in an grasslands, and deserts are all examples of ecosystems. Even | area. playgrounds and city parks are ecosystems. Ecosystems can have ‘human-made parts. The Parts of an Ecosystem | For example, ae ‘Astream is another example of an ecosystem, Like all neighborhood you live ecosystems, streams have both living and nonliving parts. The In Banco ise picture below shows some of the parts of a stream ecosystem Which of these is a nonliving part of a stream ecasystem? A fish plants B insects D water ish, insects, and plants are all living things. Choices A, B, and © ‘are incorrect. Water is not a living thing. Choice D is correct. How the Parts of an Ecosystem Interact Remember that the parts of a system interact with one another, ‘The parts of an ecosystem also interact with one another. The living things depend on boll living and nonliving things to survive, Forexample, the plants in a meadow use energy from sunlight to make food from water and gases in the air. The plants use the energy in the food to survive. Rabbits get food by eating the plants, They take in the energy stored in the plants. They use the energy to move and keep warm Like all living things, rabbits depend on the living and nonliving parts of ecosystems. A Describe two ways rabbits depend on the living parts ‘of a meadow ecosystem. B Describe two ways rabbits depend on the nonliving Parts of a meadow ecosystem. ‘The question has many possible answers, but you only need to identify two things for each part. Grass is a living part of a meadow ecosystem. Rabbits eat grass for food. They also hide in ‘grass so that other living things, such as foxes, cannot see them. Air and water are both nonliving parts of a meadow écosystern Rabbits breathe air and drink waler Energy flows through an ecosystem when organisms eat one another. Scientists use models called foed chains ta show how energy flows from one organism to another. | A food chain is a model | that shows how energy | flows through an fq | ecosystem. Bee Niele sauces ve The food chain in the diagram shows that a rabbit eats a plant and a fox eats a rabbit. Energy moves from the plant to the rabbit and from the rabbit to the fox, The arrows in a food chain show the direction that energy flaws, All food chains start with producers. Producers use energy from sunlight to make their food. Therefore, the sun is the source of energy for mast food chains on Earth. Rabbit mem esecesThe Roles of Organisms in Ecosystems Each of the living things in an ecosystem has a different role. Some living things are producers, Some are consumers. Plants and other living things that use energy from sunlight to make their own food are called producers, Producers are ve important in ecosystems. Without producers, none of the ather living things i an ecosystem would have food. Remember that animals cannot make their own food. Instead, animals get food by eating other living things. Organisms that eat, ‘or consume, other organisms are called consumers. All animals are consiimers. Some consumers are scavengers. Scavengers do not usually capture living organisms. Instead, they feed on the bodies of onganisms that are already dead. Many insects are scavengers. Some consumers are decomposers. Decompasers break down the remains of organisms into nutrients. They also break down animal wastes. Decomposers return nutrients to the soil. Plants need these nutrients to grow. Mushrooms and tiny organisms called bacteria are examples of decomposers. A scientist is studying the consumers in a cornfield ecosystem. Which of these is the scientist not studying? A beetles B com mushrooms D raccoons The question is asking which of the choiges is not a consumer Beetles, mushrooms, and raccoons all consume other organisms, ‘They are all consumers. Choices B,C, and D are incorrect. Com isa plant. Itis the only organisin in this group that uses sunlight to make its food. Com is a producer, nol a consumer Choice B is correct. A producer is an ‘organism that makes its ‘own food. A tree is a producer. ‘A consumer is an organism that gets food by eating other organisms. A bird is 2 consumer. A scavenger is an organism that eats dead organisms. A vulture is a scavenger. A decomposer is an organism that bresks down the remains or wastes of organisms. A fungus is a decomposer. You might have used the words consumer and producer before in a different way. In social studies, a producer is someone who makes @ product. A consumer is someone who buys or uses the product. LAli’s Your Turn Please read each question carefully. To answer each multiple-choice question, circle the correct response. ‘1 Which of these most likely describes the relationship between an insect and a rock in a playground ecosystem? A. The insect gets food by eating the rack. B The rock makes air for the insect to breathe, The rock makes water for the insect to drink. D_ The insect gets shelter by living under the rock. 2 A student is making a list of all the nonliving things in the park near his school. Which two things should the student ‘include in his list? A rain and trees B people and insects © rock and swing set D grass and park bench 3 Which of these describes an interaction between a and a nonliving thing in a forest ecosystem? A A mouse eats leaves. Rain washes dirt off a rack. B CA tree gets water from the soil D Sunlight makes the air warmer. “UNIT 2 Biological Sciences ©The Conner Pres nc De at dpe‘This is a short open-ended question. Write your answers on the lines. Use the picture below to answer question 4. 4 The picture shows part of a forest ecosystem. A Identify two living things and two nonliving things in this ecosystem. B Describe an interaction between two living things and an interaction between a living thing and a noni thing in this ecosystem. wl fre nc Doo ait,aed Natural and Human Changes to Ecosystems Anchors and Eligible Content 54.B.3.2.1-3; $4.8.3.3.3, 5 Ecosystems do not always stay the same. They can change for many reasons, Some changes are nalural. Some changes are caused by people. These changes can affect both the living and nonliving parts of ecosystems. They ean be harmful or helpful i ‘Changes to ecosystems affect the habitats of organisms. An organism's habitat is the place where it lives, Changes in habitats, can affect organisms in different ways. The organisms may mave to another place. They may change their behavior They may die. Changes to ecosystems can cause groups of oxanisins to A group of organisms is become extinct. A group of organisms is extinet when no more extinct if there are no members of that group are alive. Dinosaurs, dodo birds. and woolly _ living members of the mammoths are examples of animals that are extinct. There are no group. dinosaurs, dados, or woolly mammoths alive today. A living thing's habitat is where it lives. Natural ecosystem | changes caused dinosaurs and woolly | mammoths to become extinct. Human actions caused dodo birds to i There ate no dinosaurs, dodo birds, or woolly | become extinct. Mammoths alive today. They are ail extinct. Natural Changes to Ecosystems. Many changes to ecosystems happen naturally. Fires, floods, earthquakes, volcanoes, seasons, and even living things can change ecosystems. Lightning can start fires when it hits the ground. Most fires, happen in forests and grasslands. Most of them happen when the ‘weather is hot and dey. Fires can spread quickly and kill trees and other plants. Many animals get food and shelter from the plants. When a fire burns plants, the animals may have no food or shelter. Some of the animals may move to another place. Many of them die Fires can also harm the nonliving parts of an ecosystem. Ashes from the fire can float in the air for a long time. They can blow far from the fire. They block the sunlight. Plants may not have enough light. They may die. Then, the animals that eat the plants may die, 100. (UNIT 2 Bot6picat Sciences {he Central Pea he Boaat date[Ashes in the air also cause air pollution. Pollution is something that makes air, water, or soil harmful for living things. ‘Ashes in the air make: it hard for animals to breathe. Fires can bum away the plants that cover the soil. The plant roots normally hold the soil in place. When the plants die, rain can ‘wash away the soil. Without soil, new plants cannot grow. Fires are not always harmful. They can also be helpful. For example, some plants have seeds that do not burn easily. Some plants even have seeds that cannot grow unless a fire frees them froma pad, After a fire, the seeds grow into new plants. Forest fires can also be helpful for animals. As now plants grow after a fire, new animals move into the ecosystem. These animals may not have been able to live in the ecosystem before the fire ‘The fire produces new habitals for the animals and plants to live in ‘After a forest fire, new kinds of plants and animals ca move into an ecosystem. Like fires, floods are natural events that affect ecosystems. A flood happens when there is too much water ip a viver or stream. ‘The extra water flows over the sides of the river or stream, Heavy rain and melting snow cause most floods. Floods can harm ecosystems. They can destroy habitats and Kill plants and animals. They can wash away soil. Floods can also be helpful. They can carry soil to new places: and lay it down on the land, Plants grow better in the new soil Floods can also wash dead trees and bushes into the water. Fish. and other animals can use the wood for sheller or food. Earthquakes andl volcanoes can also change ecosystems. An ‘earthquake happens when huge pieces of rock below Earth's surface move, Earthquakes make the ground shake. Earthquakes can make the land change. They can make some areas of land nse. They can make other areas sink. The movement of the land can change how rivers and streams flow. It can change or destroy habitats. Voleanoes can also change ecosystems. They can make. ash and dust when they erupt. The asi and dust rise into the air. They cause air pollution. They can also block sunlight in places far from the rE ‘oe Gonenal fies be, Donel dle | ® Pollution is something that makes air, water F, OF soil harmful for living things. ba a In 2005, Hurricane Katrina hit parts of the southern United States. The hurricane caused serious floods. They damaged buildings and roads. They also destroyed many farms,volcano, With less sunlight, plants may die. Without plants, animals will die. It can be hard to know when a fire, flood, earthquake, of voleano will happen. However, the seasons change regularly. That is ‘one natural change that happens every year. When it gets cold in the winter, some animals move to warmer places. Some animals hibernate all winter Some animals grow thick layers of fur, fat, or feathers to keep warm. ‘Summers in Pennsylvania can be very hot. Animals that live in Pennsylvania in the summer have to be adapted to the heat. ‘A Name two ways an animal might be adapted to hot weather. B Describe how the adaptations you named in part A could help the animal survive in the summer. Think of ways an aniinal can keep cool. It might spend more time in the shade in the summer. It might sleep during the day and move around more at night. Part B should state how the adaptations are helptul. It is cooler in the shade. Staying in the shade helps the animal stay cool. It is also cooler at night than it is during the day. Moving around mainly at night would help the animal stay cool. Living things can also change ecosystems. For example, beavers use their teeth to cut down trees, They use the wood to build dams along rivers and streams. The dams block the flow of the rivers and streams. Ponds form behind the dams. Beaver ponds can flood the land and hat plants and animals that live there. However, over time, they can become habitats for many living things. Plants, fishes, frogs, and birds may live in beaver ponds ©The Cont Paes Ie. Bo ot peste _ UNIT 2 Biclogical Sciences” In 1815, a huge volcano called Tambora erupted in the Indian Ocean. It sent large amounts of ash and dust into the air. The ash and dust blocked sunlight all around the world. In 1816, it was so cold in ‘the northeastern United States that it snowed in some areas in June. LoteChanges Caused by People People cause many changes to ecosystems. People can cause fires, floods, and pollution, They can destray habitats and cause organisms to become extinet Many people like to walk and camp in the woods. They may build small fires when they camp. Ifthe people are nat careful when they make fires, the fires can spread. They can burn down a whole forest, People can also cause fires when they throw burning cigarettes on the ground. People’s actions can also cause floods. People build dams. The dains block the flow of rivers and streams, The water builds up behind the dam and floods the land around it.The flooding destroys habitats. People can also cause floods by building roads and parking Jots. Normally, soil soaks up rainwater When people cover the soil ‘with roads or parking lols, the soil can’t soak up the rain. The water runs off the roads and parking lots, It flows into rivers and causes floods, When people do not recycle or throw trash away properly, the trash can build up in the environment. Trash in the environment is called litter. Litter such as plastic bags can choke animals. If animals eat litter, they can become sick or die. When rain falls on the land, it can wash litter into streams and rivers. I can also wash harmful chemicals into streams and rivers The chemicals come from farms, factories, and even people's homes. Some of these chemicals cause water pollution. Much of the rain that falls on an area of land eventually flows. into a river. The land from which water drains into a river is called the river's watershed, Water can carry pollutioa from ane part of a ‘watershed to the rest of the watershed, Polluted water in a river eventually reaches the ocean. The chemicals farmers spray on fields ‘can wash into streams and rivers. The Contos Pest a Dot cupeate, B In 1988, forest fires burned parts of Yellowstone National Park. The fires burned an area of land almost ten ‘times the size of Philadelphia. Lightning started most of the fires. People started the rest. The fires killed many plants and animals. After tthe fire, new plants and animals began to live in the burned areas. Trash and chemicals are not the only things that can be pollution. Even light and sound can be pollution if they make it hard for living things to survive, Litter is trash in the ‘environment. You can learn more about watersheds in Unit 4, Lesson 4,Chemicals from the farm flow into the stream. The stream flows to the ocean. What will most likely happen when the chemicals get to the ocean? A People will use them to run large ships. B They will make the ocean water cleaner. € They will kill plants and animals in the ocean D Animals in the ocean will learn to use them for food ‘The chemicals in the water are water pollution. Peaple cannot use water pollution to rum large ships. Choice A is incorrect. Pollution makes water dirty, not clean. Choice B is ineoneet. Animals cannot use pollution for food. Choice D is incorrect. Pollution can kill plants and animals, Choice C is correct. Chemicals from farms, factories, and homes can also cause soil pollution. They can kill organisms that live in the soil. They can make it hard for plants to grow in the soil Peaple also cause air pollution. Many people drive cars anid trucks. Cars and trucks butn gasoline, When gasoline burns, it produces air pollution. People bum coal, oil, and natural gas to produce electricity, People also bum these fuels to heat their homes. When these fuels burn, they produce air pollution. Another way people change ecosystems is by bringing new plants and animals into an ecosystem, The new plants and animals may bring diseases with them. The diseases may kill the plants and animals that normally live in the ecosystern. The new plants and animals might also use food and water that other organisms need 2 to survih population from growing too large. Most plants and animals that that belongs in an area, people move to new areas do not have natural predators in the An introduced organism new environment. Without predators, a population of organisms: is one which people can spread out of control. bring to an ecosystem - | where it does not Purple loosestrife is a plant that people brought to the United Eelongireaple States. thas taken over many wetlands. The plant uses tesources | introduced some that native wetland plants need to survive. This can keep native | organisms, such as zebra plants from growing. Purple loosestrife also affects animals. It is less mussels, by accident. nutritious for animals than native plants. They introduced other organisms, such as starlings, on purpose. In an ecosystem, a native organism has predators that keep its | A native organism is one (©The Conn Pres nc Do nat dacaI's Your Turn Please read each question carefully. To answer each multiple-choice question, circle the correct response, Use the picture below to answer question 1, 1 How will the object the beavers are building most likely affect the ecosystem? A. [twill form a pond of still water, B It will stop floods fram happening. [twill make the number of trees go up. D_ Itwill make the stream run more quickly. 2 itis cold and snowy in many parts of Pennsylvania in the winter. How would the cold and snow most likely affect an animal that eats mostly grass? A [twill have less food. B It will have less water. [twill not be able to find shelter. Dt will nat be able to find a mate. Se Ez a5 OTe Coven es x. enue dieUse the picture below to answer question 3. 3 A person pours gasoline onto the ground. What wi likely happen if the gasoline gets into the water? A The water will flow more quickly. B Trees that use the water will grow taller, More fish will be able to live in the water. D People will get sick fram drinking the water. Use the information below to answer question 4, WATER MILFOIL People brought a water plant called Eurasian water milfoil from Asia to the United States. Many people use the plants in aquariums, When people clean their aquariums, they wash the plants down the drain, If even part of one of the plants survives, it can grow and reproduce in the environment. 4 What is the most likely effect of Eurasian water mil natural environment? A. It competes with animals for food. B It uses resources that native plants need. Cit provides more resources for humans D_ It helps plants in the environment grow “UNIT 2 Biological sciences The Comceatal Ps, ix, Dore ceeThis is a short open-ended question. Write your answers on the lines. Use the picture below to answer question 5. 5 A thunderstorm causes a lot of water to enter a river. The extra water makes the river flood. A What are two ways a flood can be harmful to the plants that live near the river? B What is one way a flood can be helpful to the plants that live near the river? © THe Camino Pres nc Do st pct,Agriculture Anchor and Eligible Content $4. Most of the things we use every day come from plants and animals. We get food from plants and animals. We also use them to e make clothes and other products, Plants and animals are examples of natural resources. Land is another important natural resource. We use land for many different things. We build homes and other buildings on land, We build roads on land so we can move around easily, We also use land for fun activities, such as hiking, camping, and playing sports. Most people live in cities. A city has many buildings, people, slores, and streets, Cities are known as urban areas. Many people live in areas around cities, The area around a city is called a suburban area. A suburban area has fewer buildings, people, and streets than an urban area. Few people live on most af the rest of the land. An area where fewer people live is known as a rural area, People use most of the land in a nuiral area for farming. You can learn more about natural resources in Unit 4, Lesson 2. People use land in different ways in urban, suburban, and rural areas. Agriculture Most of our food, fibers for clothing, and many other products come from plants and animals that people raise on farms. The science of growing plants and animals on farms is called agriculture. People all over the world rely on agriculture for food, clothing, and other products. } Agriculture is the science ‘of growing plants and nimals on fz You probably know that people grow com to eat and to feed to a Bis animals. However, people can use corn in other ways as well. They use some corm to make ethanol. Ethanol can be used asa fuel to | replace gasoline in some cars and trucks. People also use com to make sweeteners, cosmetics, and cleansers. They can even use corn to make some new kinds of plasties. iii 2 (Oe Conran re ie. Dt eae