Understand how living things function and how they interact with one another and their environment.

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1 District of Columbia Public Schools Essential Knowledge and Skills for Science (Grade 7) SCIENCE, Grade 7: Life Science Content Standard 2: Understand how living things function and how they interact with one another and their environment. The student should know that: One of the most general distinctions among organisms is between plants, which use sunlight to make their own food, and animals, which consume energy-rich foods. Some kinds of organisms, many of them microscopic, cannot be neatly classified as wither plants or animals. Animals and plants have a great variety of body plans and internal structures that contribute to their being able to make or find food and reproduce. SE/TE: Can You Organize a Junk Drawer? 42; Classifying 47 SE/TE: Will Mosses Absorb Water? 256; Masses of Mosses 261; Which Plant Part Is It? 262; A Closer Look at Flowers ; How Do Snakes Feed? 287 SE/TE: Guided Reading 2.2; Section Summary 2.2; Review and Reinforce 2.2; Enrich 2.2; Transparency LS13; TECH: Student Edition on Audio CD 2.2; PresentationEXPRESS CD-ROM 2.2; scn-0113 SE/TE: , , , , , , , , , Guided Reading 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Section Summary 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Review and Reinforce 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Enrich 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 TECH: Student Edition on Audio CD 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Lab Zone Easy Planner A Closer Look at Flowers; Lab Activity Video A Closer Look at Flowers 1

2 (Continued) Animals and plants have a great variety of body plans and internal structures that contribute to their being able to make or find food and reproduce. Similarities among organisms are found in internal anatomical features, which can be used to infer the degree of relatedness among organisms. In classifying organisms, biologists consider details of internal and external structures to be more important than behavior or general appearance. (Continued) SE/TE: Can You Organize a Junk Drawer? 42; Classifying 47 (Continued) TECH: PresentationEXPRESS CD-ROM 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 SE/TE: Guided Reading 2.2; Section Summary 2.2; Review and Reinforce 2.2; Enrich 2.2; Transparency LS13; TECH: Student Edition on Audio CD 2.2; PresentationEXPRESS CD-ROM 2.2; scn-0113 For sexually reproducing organisms, a species comprises all organisms that can mate with one another to produce fertile offspring SE/TE: Spreading Spores 259 SE/TE: 220, 238, 254, 259, 263, , , 297, 307, 315, 376, 411, 675 Guided Reading 8.4; Section Summary 8.4; Review and Reinforce 8.4; Enrich 8.4 TECH: Student Edition on Audio CD 8.4; PresentationEXPRESS CD-ROM 8.4 In some kinds of organisms, all the genes come from a single parent, whereas in organisms that have sexes, typically half of the genes come from each parent. SE/TE: What Does the Father Look Like? 110; What s the Chance? 118; Which Chromosome is Which? 126; Family Puzzle SE/TE: , , , , 220, 237, 297, 305, 309, 310, 315 Guided Reading 4.1, 4.2, 4.3, 5.1; Section Summary 4.1, 4.2, 4.3, 5.1; Review and Reinforce 4.1, 4.2, 4.3, 5.1; Enrich 4.1, 4.2, 4.3, 5.1 TECH: Student Edition on Audio CD 4.1, 4.2, 4.3, 5.1; Lab Zone Easy Planner Family Puzzle; Lab Activity Video Family Puzzle; PresentationEXPRESS CD-ROM 4.1, 4.2, 4.3, 5.1 2

3 In sexual reproduction, a single specialized cell from a female merges with a specialized cell from a male. As the fertilized egg, carrying genetic information from each parent, multiples to form the complete organism with about a trillion cells, the same genetic information is copied in each cell. Living Environment SE/TE: What s the Chance? 118; Which Chromosome is Which? 126; Spreading Spores 259 SE/TE: 220, 238, 254, 259, 263, , , 297, 307, 315, 376, 411, 675 Guided Reading 8.4; Section Summary 8.4; Review and Reinforce 8.4; Enrich 8.4 TECH: Student Edition on Audio CD 8.4; PresentationEXPRESS CD-ROM 8.4 Cells All living things are composed of cells, from just one to many millions, whose details usually are visible only through a microscope. Different body tissues and organs are made up of different kinds of cells. The cells are similar tissues and organs in other animals are similar to those in human beings but differ somewhat from cells found in plants Within cells, many of the basic functions of organisms such as extracting energy from food and getting rid of waste are carried out. The way in which cells function is similar in all living organisms. SE/TE: Is Seeing Believing? 50; How Large Are Cells? 60; Gelatin Cell 62 SE/TE: Where Does the Energy Come From? 86; What Are the Yeast Cells Doing? 95; Modeling Mitosis 96; Multiplying and Dividing 103 SE/TE: 50-59, Guided Reading 2.3, 2.4; Section Summary 2.3, 2.4; Review and Reinforce 2.3, 2.4; Enrich 2.3, 2.4; Transparency LS15, LS17, LS18; TECH: Student Edition on Audio CD 2.3, 2.4; PresentationEXPRESS CD-ROM 2.3, 2.4; scn-0311 SE/TE: 74-79, 80-85, 86-90, 91-94, Guided Reading 3.1, 3.2, 3.3, 3.4, 3.5; Section Summary 3.1, 3.2, 3.3, 3.4, 3.5; Review and Reinforce 3.1, 3.2, 3.3, 3.4, 3.5; Enrich 3.1, 3.2, 3.3, 3.4, 3.5 TECH: Student Edition on Audio CD 3.1, 3.2, 3.3, 3.4, 3.5; Lab Zone Easy Planner Multiplying and Dividing; Lab Activity Video Multiplying and Dividing; PresentationEXPRESS CD-ROM 3.1, 3.2, 3.3, 3.4, 3.5 3

4 About two thirds of the weight of cells is accounted for by water, which gives cells many of their properties. SE/TE: What Is a Compound? 74 SE/TE: 75 Guided Reading 3.1; Section Summary 3.1; Review and Reinforce 3.1; Enrich 3.1; Transparency LS21; TECH: Student Edition on Audio CD 3.1; PresentationEXPRESS CD-ROM 3.1; scn-0313 Cells continually divide to make more cells for growth and repair. Various organs and tissues function to serve the needs of cells for food, air, and waste removal. Organs and organ systems are composed of cells and help to provide all cells with basic needs. SE/TE: Where Does the Energy Come From? 86; What Are the Yeast Cells Doing? 95; Modeling Mitosis 96; Multiplying and Dividing 103 SE/TE: 80-85, 86-90, 91-94, Guided Reading 3.2, 3.3, 3.4, 3.5; Section Summary 3.2, 3.3, 3.4, 3.5; Review and Reinforce 3.2, 3.3, 3.4, 3.5; Enrich 3.2, 3.3, 3.4, 3.5 TECH: Student Edition on Audio CD 3.2, 3.3, 3.4, 3.5; Lab Zone Easy Planner Multiplying and Dividing; Lab Activity Video Multiplying and Dividing; PresentationEXPRESS CD-ROM 3.2, 3.3, 3.4, 3.5 SE/TE: 295 Guided Reading 9.1; Section Summary 9.1; Review and Reinforce 9.1; Enrich 9.1 TECH: Student Edition on Audio CD 9.1; PresentationEXPRESS CD-ROM 9.1 4

5 Like other animals, human beings have body systems for obtaining and providing energy, defense, reproduction, and the coordination of body functions. For the body to use food for energy and building materials, the food must first be digested into molecules that are absorbed and transported to cells. SE/TE: Hard as a Rock? 474; How Do Muscles Work? 482; A Look Beneath the Skin 487; How Can You Speed Up Digestion 516; As the Stomach Churns 522; How Hard Does Your Heart Work? 534; How Big Can You Blow Up a Balloon? 564 SE/TE: How Can You Speed Up Digestion 516; As the Stomach Churns 522 SE/TE: , , , , , , , , Guided Reading 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2; Section Summary 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2; Review and Reinforce 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2; Enrich 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2 TECH: Student Edition on Audio CD 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2; Lab Zone Easy Planner As the Stomach Churns; Lab Activity Video As the Stomach Churns; PresentationEXPRESS CD-ROM 14.2, 14.3, 15.2, 16.1, 17.1, 17.2, 19.1, 20.1, 20.2 SE/TE: , , Guided Reading 15.1, 15.2, 15.3,; Section Summary 15.1, 15.2, 15.3; Review and Reinforce 15.1, 15.2, 15.3; Enrich 15.1, 15.2, 15.3 TECH: Student Edition on Audio CD 15.1, 15.2, 15.3; Lab Zone Easy Planner As the Stomach Churns; Lab Activity Video As the Stomach Churns; PresentationEXPRESS CD-ROM 15.1, 15.2,

6 To burn food for the release of energy stored in it, oxygen must be supplied to cells and carbon dioxide removed. Lungs take in oxygen for the combustion of food and they eliminate the carbon dioxide produced. The urinary system disposes of dissolved waste molecules, the intestinal tract removes solid wastes and the skin and lungs rid the body of heat energy. The circulatory system moves all of these substances to or from cells where they are needed or produced, responding to changing demands. SE/TE: How Can You Speed Up Digestion 516; As the Stomach Churns 522; How Hard Does Your Heart Work? 534; How Big Can you Blow Up a Balloon? 564 SE/TE: , , , , Guided Reading 15.1, 15.2, 15.3, 16.1, 17.1; Section Summary 15.1, 15.2, 15.3, 16.1, 17.1; Review and Reinforce 15.1, 15.2, 15.3, 16.1, 17.1; Enrich 15.1, 15.2, 15.3, 16.1, 17.1 TECH: Student Edition on Audio CD 15.1, 15.2, 15.3, 16.1, 17.1; Lab Zone Easy Planner As the Stomach Churns; Lab Activity Video As the Stomach Churns; PresentationEXPRESS CD-ROM 15.1, 15.2, 15.3, 16.1, 17.1 Specialized cells and the molecules they produce identify and destroy microbes that get inside the body. SE/TE: Which Pieces Fit Together? 597 SE/TE: Guided Reading 18.2; Section Summary 18.2; Review and Reinforce 18.2; Enrich 18.2; Transparency LS175; TECH: Student Edition on Audio CD 18.2; Lab Zone Easy Planner ; Lab Activity Video ; PresentationEXPRESS CD-ROM 18.2; PHSchool.com cep

7 Hormones are chemicals from glands that affect other body parts. They are involved in helping the body respond to danger and in regulating human growth, development and reproduction. SE/TE: What s the Signal? 666; Growing Up 691 SE/TE: , Guided Reading 20.1, 20.2; Section Summary 20.1, 20.2; Review and Reinforce 20.1, 20.2; Enrich 20.1, 20.2; Transparency LS192, LS193, LS195, LS916, LS197; TECH: Student Edition on Audio CD 20.1, 20.2; Lab Zone Easy Planner Growing Up; Lab Activity Video Growing Up; PresentationEXPRESS CD-ROM 20.1, 20.2; PHSchool.com cep4071; scn-0472 Interactions among the senses, nerves and brain make possible the learning that enables human beings to cope with changes in the environment. Human beings have many similarities and differences. The similarities make it possible for people to reproduce and donate blood and organs to one another throughout the world. Their differences enable them to create diverse social and cultural arrangements and to solve problems in a variety of ways. SE/TE: How Simple Is a Simple Task? 626; Ready or Not! 631; How Does Your Knee React? 632; What s in the Bag? 642 SE/TE: , , Guided Reading 19.1, 19.2, 19.3; Section Summary 19.1, 19.2, 19.3; Review and Reinforce 19.1, 19.2, 19.3; Enrich 19.1, 19.2, 19.3 TECH: Student Edition on Audio CD 19.1, 19.2, 19.3; Lab Zone Easy Planner Ready or Not!; Lab Activity Video Ready or Not!; PresentationEXPRESS CD-ROM 19.1, 19.2, 19.3 SE/TE: Guided Reading 14.1; Section Summary 14.1; Review and Reinforce 14.1; Enrich 14.1 TECH: Student Edition on Audio CD 14.1; PresentationEXPRESS CD-ROM 14.1; scn

8 In all environments freshwater, marine, forest, desert, grassland, mountain, and others organisms with similar needs may compete with one another for resources, including food, space, water, air, and shelter. In any particular environment, the growth and survival of organisms depend on the physical conditions. One of the most general distinctions among organisms is between plants, which use sunlight to make their own food, and animals, which consume energy-rich foods. Some kinds of organisms, many of them microscopic, cannot be neatly classified as either plants or animals. SE/TE: What s the Scene? 704; Counting Turtles 719; Can You Hide a Butterfly? 722 SE/TE: Can You Organize a Junk Drawer? 42; Classifying 47 SE/TE: , Guided Reading 21.1, 21.3; Section Summary 21.1, 21.3; Review and Reinforce 21.1, 21.3; Enrich 21.1, 21.3 TECH: Student Edition on Audio CD 21.1, 21.3; Lab Zone Easy Planner Counting Turtles 719; Lab Activity Video Counting Turtles 719; PresentationEXPRESS CD-ROM 21.1, 21.3 SE/TE: Guided Reading 2.2; Section Summary 2.2; Review and Reinforce 2.2; Enrich 2.2; Transparency LS13; TECH: Student Edition on Audio CD 2.2; PresentationEXPRESS CD-ROM 2.2; scn

9 Food provides the fuel and the building material for all organisms. Plants use the energy from light to make sugars from carbon dioxide and water. This food can be used immediately or stored for later use. Organisms that eat plants break down the plant structures to produce the materials and energy they need to survive. Then they are consumed by other organisms. SE/TE: Will Mosses Absorb Water? 256; Masses of Mosses 261; Which Plant Part Is It? 262; A Closer Look at Flowers ; How Do Snakes Feed? 287 SE/TE: , , , , , , , , , Guided Reading 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Section Summary 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Review and Reinforce 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Enrich 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 TECH: Student Edition on Audio CD 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Lab Zone Easy Planner A Closer Look at Flowers; Lab Activity Video A Closer Look at Flowers; PresentationEXPRESS CD-ROM 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 Two types of organisms may interact with one another in several ways: They may be in a producer/consumer, predator/prey, or parasite/host relationship. Or one organism may scavenge or decompose another. Relationships may be competitive or mutually beneficial. Some species have become so adapted to each other that neither could survive without the other. SE/TE: Can You Hide a Butterfly? 722 SE/TE: Guided Reading 21.3; Section Summary 21.3; Review and Reinforce 21.3; Enrich 21.3 TECH: Student Edition on Audio CD 21.3; PresentationEXPRESS CD-ROM

10 Over a long time, matter is transferred from one organism to another repeatedly and between organisms and their physical environment. As in all material systems, the total amount of matter remains constant, even though its form and location change. Energy can change from one form to another in living things. Animals get energy from oxidizing their food, releasing some of its energy as heat. Almost all food energy comes originally from sunlight. SE/TE: Where Did Your Dinner Come From? 740; Are You Part of a Cycle? 746; Biomes in Miniature SE/TE: Where Did Your Dinner Come From? 740; Are You Part of a Cycle? 746; Biomes in Miniature SE/TE: , Guided Reading 22.1, 22.2; Section Summary 22.1, 22.2; Review and Reinforce 22.1, 22.2; Enrich 22.1, 22.2; Transparency LS12, LS13, LS15, LS16, LS17 TECH: Student Edition on Audio CD 22.1, 22.2; Lab Zone Easy Planner Biomes in Miniature; Lab Activity Video Biomes in Miniature; PresentationEXPRESS CD- ROM 22.1, 22.2; PHSchool.com CFP- 4024; scn-0521 SE/TE: , Guided Reading 22.1, 22.2; Section Summary 22.1, 22.2; Review and Reinforce 22.1, 22.2; Enrich 22.1, 22.2; Transparency LS12, LS13, LS15, LS16, LS17 TECH: Student Edition on Audio CD 22.1, 22.2; Lab Zone Easy Planner Biomes in Miniature; Lab Activity Video Biomes in Miniature; PresentationEXPRESS CD- ROM 22.1, 22.2; PHSchool.com CFP- 4024; scn

11 All organisms, including humans are part of and depend on two main interconnected global food webs. One includes microscopic ocean plants, the animals that feed on them, and finally the animals that feed on those animals. The other web includes land plants, the animals that feed on them and so forth. The cycles continue indefinitely because organisms decompose after death and return food material to the environment. SE/TE: Are You Part of a Cycle? 746 SE/TE: 742, 743, 745 Guided Reading 22.1; Section Summary 22.1; Review and Reinforce 22.1; Enrich 22.1; Transparency LS12, LS13; TECH: Student Edition on Audio CD 22.1; Lab Zone Easy Planner ; Lab Activity Video ; PresentationEXPRESS CD-ROM 22.1; scn-0521 Heredity For sexually reproducing organisms, a species comprises all organisms that can mate with one another to produce fertile offspring. SE/TE: Spreading Spores 259 SE/TE: 220, 238, 254, 259, 263, , , 297, 307, 315, 376, 411, 675 Guided Reading 8.4; Section Summary 8.4; Review and Reinforce 8.4; Enrich 8.4 TECH: Student Edition on Audio CD 8.4; PresentationEXPRESS CD-ROM 8.4 In some kinds of organisms, all the genes come from a single parent, whereas in organisms that have sexes, typically half of the genes come from each parent. SE/TE: What Does the Father Look Like? 110; What s the Chance? 118; Which Chromosome is Which? 126; Family Puzzle SE/TE: , , , , 220, 237, 297, 305, 309, 310, 315 Guided Reading 4.1, 4.2, 4.3, 5.1; Section Summary 4.1, 4.2, 4.3, 5.1; Review and Reinforce 4.1, 4.2, 4.3, 5.1; Enrich 4.1, 4.2, 4.3, 5.1 TECH: Student Edition on Audio CD 4.1, 4.2, 4.3, 5.1; Lab Zone Easy Planner Family Puzzle; Lab Activity Video Family Puzzle; PresentationEXPRESS CD-ROM 4.1, 4.2, 4.3,

12 In sexual reproduction, a single specialized cell from a female merges with a specialized cell from a male. As the fertilized egg, carrying genetic information from each parent, multiplies to form the complete organism with about a trillion cells, the same genetic information is copied in each cell. Animals and plants have a great variety of body plans and internal structures that contribute to their being able to make or find food and reproduce. Similarities among organisms are found in internal anatomical features, which can be used to infer the degree of relatedness among organisms. In classifying organisms, biologists consider details of internal and external structures to be more important than behavior or general appearance SE/TE: What s the Chance? 118; Which Chromosome is Which? 126; Spreading Spores 259 SE/TE: Will Mosses Absorb Water? 256; Masses of Mosses 261; Which Plant Part Is It? 262; A Closer Look at Flowers ; How Do Snakes Feed? 287 SE/TE: Can You Organize a Junk Drawer? 42; Classifying 47 SE/TE: 220, 238, 254, 259, 263, , , 297, 307, 315, 376, 411, 675 Guided Reading 8.4; Section Summary 8.4; Review and Reinforce 8.4; Enrich 8.4 TECH: Student Edition on Audio CD 8.4; PresentationEXPRESS CD-ROM 8.4 SE/TE: , , , , , , , , , Guided Reading 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Section Summary 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Review and Reinforce 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Enrich 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 TECH: Student Edition on Audio CD 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3; Lab Zone Easy Planner A Closer Look at Flowers; Lab Activity Video A Closer Look at Flowers; PresentationEXPRESS CD-ROM 8.1, 8.2, 8.3, 8.4, 8.5, 11.2, 11.3, 11.4, 12.1, 12.3 SE/TE: Guided Reading 2.2; Section Summary 2.2; Review and Reinforce 2.2; Enrich 2.2; Transparency LS13; TECH: Student Edition on Audio CD 2.2; PresentationEXPRESS CD-ROM 2.2; scn

13 Small differences between parents and offspring can accumulate (through selective breeding) in successive generations so that descendants are very different from their ancestors. SE/TE: How Do Living Things Vary? 172; Nature at Work 180; How Can You Classify Species? 182; Telltale Molecules 188 SE/TE: , Guided Reading 6.1, 6.2; Section Summary 6.1, 6.2; Review and Reinforce 6.1, 6.2; Enrich6.1, 6.2 ; Transparency LS51, LS53; TECH: Student Edition on Audio CD 6.1, 6.2; Lab Zone Easy Planner Telltale Molecules; Lab Activity Video Telltale Molecules; PresentationEXPRESS CD- ROM 6.1, 6.2; scn- 0351, scn-0352 Individual organisms with certain traits are more likely than others to survive and have offspring. Changes in environmental conditions can affect the survival of individual organisms and entire species. Many thousands of layers of sedimentary rock provide evidence for the long history of the earth and for the long history of changing life forms whose remains are found in the rocks. More recently deposited rock layers are more likely to contain fossils resembling existing species. SE/TE: Nature at Work 180 SE/TE: SE/TE: What Can You Learn From Fossils? 189 SE/TE: Guided Reading 6.1; Section Summary 6.1; Review and Reinforce 6.1; Enrich 6.1; Transparency LS51; TECH: Student Edition on Audio CD 6.1; Lab Zone Easy Planner Nature at Work; Lab Activity Video Nature at Work; PresentationEXPRESS CD-ROM 6.1; scn-0351 Guided Reading 6.3; Section Summary 6.3; Review and Reinforce 6.3; Enrich 6.3; Transparency LS54, LS55, LS56; TECH: Student Edition on Audio CD 6.3; PresentationEXPRESS CD-ROM 6.3; PHSchool.com cdp

14 Fossil evidence is consistent with the idea that human beings evolved from earlier species. SE/TE: What Can You Learn From Fossils? 189 SE/TE: Guided Reading 6.3; Section Summary 6.3; Review and Reinforce 6.3; Enrich 6.3; Transparency LS54, LS55, LS56; TECH: Student Edition on Audio CD 6.3; PresentationEXPRESS CD-ROM 6.3; PHSchool.com cdp-3053 Reference: document provided in Hardcopy: DCPS SCIENCE STANDARDS FOR TEACHING AND LEARNING, Revised and Reformatted June 2004, DRAFT, pp (actual) 14

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