Life ScienceLife Science by Kim Fieldsby Kim Fields GenreGenre Comprehension SkillComprehension Skill Text FeaturesText Features Science ContentScience Content Nonfi ctionNonfi ction Compare andCompare and • Captions• Captions PlantsPlants ContrastContrast • Glossary• Glossary Scott Foresman Science 3.1Scott Foresman Science 3.1 ì<(sk$m)=bdiaib<ì<(sk$m)=bdiaib<ISBNISBN 0-328-13808-80-328-13808-8 +^-Ä-U-Ä-U+^-Ä-U-Ä-U
Vocabulary What did you learn?Plants and How They Grow coniferous 1. How do roots help a plant stay alive? deciduous 2. What are some different ways that seeds areby Kim Fields extinct scattered to make new plants? fossil 3. How have plants changed over time? germinate 4. In this book, you have read about pollination. Write to explain how pollinate petals help pollination. Use details from the seed leaf book as you write. seedling 5. Compare and Contrast How are deciduous and coniferous trees alike? How are system they different? Illustration: 7 Alan Barnard; 17 Alan Barnard; 23 Alan Barnard Photographs: Every effort has been made to secure permission and provide appropriate credit for photographic material. The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions. Unless otherwise acknowledged, all photographs are the property of Scott Foresman, a division of Pearson Education. Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd). Title Page: ©Lou Jacobs Jr./Grant Heilman Photography; 2 ©John Warden/Index Stock Imagery; 4 ©DK Images; 5 (R) Silver Burdett Ginn, (CL) ©DK Images; 8 ©Lou Jacobs Jr./Grant Heilman Photography; 9 ©DK Images; 10 ©DK Images; 11 (T) ©Jeff Lepore/Photo Researchers, Inc., (B) ©Stone/Getty Images; 12 ©Carolina Biological/Visuals Unlimited; 13 (CR) ©DK Images, (TL) ©Brad Mogen/Visuals Unlimited; 14 (TL) ©John Poutier/Maxx Images, Inc., (TR) ©Darryl Torckler/Getty Images; 15 (TL) ©Brian Gordon Green/NGS Image Collection, (TR) ©Jorg & Petra Wegner/Animals Animals/Earth Scenes; 16 ©Nigel Cattlin/Photo Researchers, Inc.; 18 (BR) ©Kenneth W. Fink/Photo Researchers, Inc., (CC) ©DK Images, (TR) ©Nigel Cattlin/Photo Researchers, Inc.; 19 Nigel Cattlin/Holt Studios; 20 (CL) Neg./Transparency No. K13073. Courtesy Dept. of Library Services/American Museum of Natural History, (BC) ©John Cancalosi/Peter Arnold, Inc., (CR) ©Dr. E. R. Degginger/Color-Pic, Inc.; 21 ©David Muench/ Muench Photography, Inc; 22 (T) ©The Natural History Museum, London, (C) ©Wolfgang Kaehler/Corbis. ISBN: 0-328-13808-8 Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America. This publication is protected by Copyright and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permissions, write to: Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025. 3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05
What are the main parts Plants come in all sizes and shapes. They can grow almost anywhere. Each plant needs special things of a plant? to grow. Most plants have four parts. Roots, a stem, flowers, and leaves are the four main parts. What All Living Things Need Living things have needs. Plants and animals need food, air, water, and space to live and grow. Animals need to find food to eat. Plants are different. They can make their own food. Plants use energy from the Sun to make food. These black-eyed This Alaskan Susans make their brown bear is own food. looking for food. 2 3
Why Plants Need Leaves Other Ways Leaves Help Plants Plants need leaves to make food. The leaves make Leaves also help a plant take in water. Leaves can a type of sugar. A plant’s leaves are a part of its leaf let out extra water through tiny holes. A plant that system. A system has parts that work together. lives in dry places may have fuzzy leaves. This helps Carbon dioxide gas enters a plant through holes keep water inside the plant. in the leaves. Water enters a plant through the roots Some leaves help keep the plant and stem. Leaves also take in sunlight. Water and alive. Leaves can be tough or sharp. carbon dioxide are changed into sugar and oxygen. They can be filled with poison. Energy from sunlight does this. The sugar is the These leaves keep animals from plant’s food. The oxygen goes out through holes in eating them. the leaves. Oxygen Oxygen Carbon Dioxide comes out. Carbon dioxide Sunlight This is what a goes in. Sunlight plant needs to goes in. make food. Water Water goes in. Sugar The oak leaf is different from Sugar goes the leaves on a fir tree. 4 to roots. 5
Why do plants need There are small root hairs at the tips of roots. Roots with their many hairs grow deep into the soil. These roots and stems? hairs take in water for the plant. Tubes carry water to the stem and leaves. The Sun How Roots Help Plants can dry out a plant. On hot days, roots take in water Roots hold plants in the to replace what is lost. Water moves from the ground. They store food for root hairs into the root. Then it travels up to the the plant. Roots draw water stem and leaves. and minerals out of the soil. Root Many plants have a taproot. hair Taproots are large roots that grow deep in the soil. They store food for the plant. Have you eaten a beet or a carrot? If so, you’ve tasted a taproot! Beet Carrots Beets and carrots are roots you can eat. 6 7
How Stems Help Plants Potatoes are stem parts that grow underground. A stem holds up a plant’s leaves, fruits, and flowers. They store food for the plant. New stems can grow Its tubes move water from the roots to the leaves. from a potato’s buds. The buds are also called “eyes.” Others tubes take food from the leaves to the stem Some stems have special parts that keep plants safe. and roots. Some stems have hairs that sting animals. Other stems Some stems are thin and grow along the ground. have thorns. Both thorns and stinging hairs help keep These stems can grow roots and a new plant. animals away. Cactus stems are fat and have a thick covering. This helps keep water inside the plant. These cactus plants have thorns. The thorns are special leaves. Potatoes can be eaten. But you must dig them out of the ground. 8 9
How are plants grouped? Making Seeds Flowers have special parts that make pollen. The Flowering Plants petals of a flower attract insects or other animals. They Grasses and trees are types of plants. Trees have often move the pollen. Wind can also pollinate a a strong, woody stem to hold them up. Grasses do flower. This happens when pollen is moved to the part not have woody stems. They grow near the ground. of another flower that makes seeds. When a flower is In the fall, many grasses keep only their roots alive. pollinated, seeds form. Fruit grows around the seeds In the spring they grow a new stem with leaves. to protect them. In the fall many trees’ leaves die and fall off. These trees are deciduous. Deciduous trees grow new leaves in the spring. This bee moves pollen from another plant to the seed-making part of the flower. Pollen Seed-making part Petal These plants and trees both have flowers. The trees are tall. The plants are short. 10 11
Coniferous Trees Two Types of Cones Coniferous trees do not lose their leaves Coniferous trees make two kinds of cones. One cone all at once. They do not grow flowers. They is a small pollen cone. The other is a large seed cone. have cones that make seeds. The leaves of A seed starts to grow when pollen from the pollen these trees look like needles. Pine, spruce, cone of another tree attaches to the seed cone. Seeds hemlock, and fir are coniferous trees. fall to the ground when they are ripe. Sometimes the seeds grow into trees. Pollen from these small cones needs to reach seeds in a bigger cone. Wind makes this happen. Seed 12 13
How do new plants grow? Special Ways of Releasing Seeds Some types of cones need to be heated by a forest Scattering Seeds fire. Then the cones can release their seeds. The fire Seeds are scattered so they can grow in new places. also removes other plants around the trees. This Some seeds are scattered by water. Wind can carry makes space for the seeds to grow. seeds that are very light. Animals carry other seeds away. Sometimes animals eat the seed’s fruit. The seed passes through the animal’s body. Then it is dropped to the ground. Other seeds are scattered when they stick to an animal’s fur. A seed can blow A seed can float away in water. away in the wind. A seed can stick to fur. A seed can be eaten. 14 15
Germinating and Growing Seeds need special things to sprout, or germinate. Seeds come in different colors, sizes, and shapes. They need air, the right temperature, and enough Every seed has a tiny plant inside it. Every seed also water. When things are right, a seed sprouts. The has a seed coat. This protects the plant inside the seed. seed breaks open and a seedling, or young plant, The tiny plant can grow into a new plant. begins to grow. A young root grows down. A stem Every seed has one or more seed leaves. A seed leaf with leaves grows up. This plant uses food stored in gives food to the new plant. its seed to grow. This seed has germinated. Seed coat Tiny plant Seed leaf This seedling has sprouted. It needs water and sunlight to grow. 16 17
Life Cycle of a Plant Soon the seedling grows into an adult plant with First, a seed must germinate. Next, a flowers. The flowers are pollinated and new seeds seedling grows a root downward into the grow. If the seeds germinate they grow into new soil. Then, the seedling’s stem grows upward. plants. Then the cycle starts again. Then the stem grows leaves. Finally, the leaves use sunlight to make sugar for the plant to eat. Germinating seed This peanut plant Seedling starts out as a seed. What happens next? Seed Adult plant 18 19
How are plants from the Petrified fossils form when rock replaces plant parts. Sometimes a tree gets buried in the ground. Minerals past like today’s plants? from water replace the tree’s wood. Over a long time, the wood becomes stone. Plants That Lived Long Ago When a plant becomes extinct, none of its kind A fossil is the remains of a living thing. Fossils will ever live again. Ferns that live today are different come from plants or animals that lived long ago. from extinct ferns. We can learn about plants by studying fossils. Petrified wood fossils A fossil forms after a plant dies. The plant gets pressed into mud and rots away. The mud keeps the plant’s form. Over time, the mud hardens into rock. When the rock cracks open, you can see the fossil. Ferns These are fossils of extinct plants. Horsetail 20 21
Plants Change Over Time Magnolias are flowering plants. They have grown By studying fossils, we’ve learned that the first and changed over millions of years. Magnolias from plants did not have flowers or cones. But plants long ago kept their leaves year-round. Now, some changed over time. Trees that made cones spread over magnolias lose their leaves in the fall. But magnolia Earth. Plants with flowers started to grow. flowers have stayed the same for millions of years. Plants grow all over the Earth. They grow and live in different ways. Plants make food energy from light energy. Without them, life would be impossible! This is a fossil of a magnolia leaf. Magnolia trees grew on Earth when dinosaurs lived here. Dinosaurs are extinct. Magnolia trees are still found on Earth. Some magnolias bloom all at once in spring. Then new leaves grow. 22 23
VocabularyGlossary What did you learn? coniferousconiferous does not lose its leaves in the fall 1. How do roots help a plant stay alive? deciduousdeciduous loses its leaves in the fall 2. What are some different ways that seeds are extinct scattered to make new plants? extinct type of living thing no longer alive fossilfossil remains of a living thing from long ago 3. How have plants changed over time? germinategerminate to begin to grow 4. In this book, you have read about pollination. Write to explain how pollinatepollinate when pollen is moved to a flower part petals help pollination. Use details from the that makes seeds book as you write. seed leaf seed leaf part of a seed that provides food for the 5. Compare and Contrast How are seedling new plant deciduous and coniferous trees alike? How are system they different? seedling young plant system a set of parts that work together Illustration: 7 Alan Barnard; 17 Alan Barnard; 23 Alan Barnard Photographs: Every effort has been made to secure permission and provide appropriate credit for photographic material. The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions. Unless otherwise acknowledged, all photographs are the property of Scott Foresman, a division of Pearson Education. Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd). Title Page: ©Lou Jacobs Jr./Grant Heilman Photography; 2 ©John Warden/Index Stock Imagery; 4 ©DK Images; 5 (R) Silver Burdett Ginn, (CL) ©DK Images; 8 ©Lou Jacobs Jr./Grant Heilman Photography; 9 ©DK Images; 10 ©DK Images; 11 (T) ©Jeff Lepore/Photo Researchers, Inc., (B) ©Stone/Getty Images; 12 ©Carolina Biological/Visuals Unlimited; 13 (CR) ©DK Images, (TL) ©Brad Mogen/Visuals Unlimited; 14 (TL) ©John Poutier/Maxx Images, Inc., (TR) ©Darryl Torckler/Getty Images; 15 (TL) ©Brian Gordon Green/NGS Image Collection, (TR) ©Jorg & Petra Wegner/Animals Animals/Earth Scenes; 16 ©Nigel Cattlin/Photo Researchers, Inc.; 18 (BR) ©Kenneth W. Fink/Photo Researchers, Inc., (CC) ©DK Images, (TR) ©Nigel Cattlin/Photo Researchers, Inc.; 19 Nigel Cattlin/Holt Studios; 20 (CL) Neg./Transparency No. K13073. Courtesy Dept. of Library Services/American Museum of Natural History, (BC) ©John Cancalosi/Peter Arnold, Inc., (CR) ©Dr. E. R. Degginger/Color-Pic, Inc.; 21 ©David Muench/ Muench Photography, Inc; 22 (T) ©The Natural History Museum, London, (C) ©Wolfgang Kaehler/Corbis. ISBN: 0-328-13808-8 Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America. This publication is protected by Copyright and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permissions, write to: Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025. 3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05 24
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