TABLE OF CONTENTS Check Your Understanding................... 6 Topic 1: Planning and Carrying Out an Investigation.................... 16 Lesson 1: The Basics...................... 16 Lesson 2: Building on the Basics............. 20 Lesson 3: Beyond the Basics................ 24 Putting It All Together...................... 28 Topic 2: Using Models...................... 30 Lesson 1: The Basics...................... 30 Lesson 2: Building on the Basics............. 34 Lesson 3: Beyond the Basics................ 38 Putting It All Together...................... 42 Topic 3: Forces, Motion, and Change.......... 44 Lesson 1: The Basics...................... 44 Lesson 2: Building on the Basics............. 48 Lesson 3: Beyond the Basics................ 52 Putting It All Together...................... 56 Topic 4: The Periodic Table and Chemical Reactions................. 58 Lesson 1: The Basics...................... 58 Lesson 2: Building on the Basics............. 62 Lesson 3: Beyond the Basics................ 66 Putting It All Together...................... 70 Texas Essential Knowledge and Skills (TEKS) 8.2(A), 8.2(B), 8.2(C), 8.2(D), 8.2(E), 8.3(A), 8.3(B), 8.3(C), 8.4(A) 8.2(A), 8.3(B), 8.3(C), 8.7(A) 8.6(A), 8.6(B), 8.6(C) 8.5(A), 8.5(B), 8.5(C), 8.5(D), 8.5(E), 8.5(F) 4
Topic 5: Energy and Its Changes.............. 72 Lesson 1: The Basics...................... 72 Lesson 2: Building on the Basics............. 76 Lesson 3: Beyond the Basics................ 80 Putting It All Together...................... 84 Topic 6: Genes and Inheritance............... 86 Lesson 1: The Basics...................... 86 Lesson 2: Building on the Basics............. 90 Lesson 3: Beyond the Basics................ 94 Putting It All Together...................... 98 Topic 7: Species and Change............... 100 Lesson 1: The Basics..................... 100 Lesson 2: Building on the Basics............ 104 Lesson 3: Beyond the Basics............... 108 Putting It All Together..................... 112 Topic 8: Weather and Climate............... 114 Lesson 1: The Basics..................... 114 Lesson 2: Building on the Basics............ 118 Lesson 3: Beyond the Basics............... 122 Putting It All Together..................... 126 Topic 9: Forces That Change Earth s Surface.. 128 Lesson 1: The Basics..................... 128 Lesson 2: Building on the Basics............ 132 Lesson 3: Beyond the Basics............... 136 Putting It All Together..................... 140 Topic 10: Earth, the Moon, and the Sun....... 142 Lesson 1: The Basics..................... 142 Lesson 2: Building on the Basics............ 146 Lesson 3: Beyond the Basics............... 150 Putting It All Together..................... 154 6.8(A), 6.9(C) 7.14(A), 7.14(B), 7.14(C) 8.11(B), 8.14(C) 8.10(A), 8.10(B), 8.10(C) 8.9(A), 8.9(B), 8.9(C) 8.8(A), 8.8(B), 8.8(D), 8.8(E) Glossary................................ 156 5
CHECK YOUR UNDERSTANDING Read each question carefully. Choose the best answer for each question. Mark your answer on your answer sheet. If you do not know the answer to a question, you can skip it and come back to it later. 1. Scientist use models to describe atoms because A. atoms are too dangerous to observe directly. B. models look better than real atoms. C. atoms are not real but models are. D. atoms are too small to observe directly. 3. According to the law of conservation of matter, in a chemical reaction, A. matter is never lost or gained. B. matter keeps its original properties. C. atoms cannot combine into different kinds of matter. D. heat energy is always given off. 2. Frank and Jerry are moving a refrigerator. Frank pushes with a certain force in one direction. Jerry pushes with half the amount of force in the opposite direction. How will the refrigerator MOST LIKELY move? A. The refrigerator will move in the direction in which Frank is pushing. B. The refrigerator will move in the direction in which Jerry is pushing. C. The refrigerator will not move. D. The refrigerator will fall over. 4. Radiation is the transfer of energy by A. motion. B. waves. C. liquid currents. D. work. 5. Which of the following is a diagram used to find the possible traits of offspring? A. Punnett square B. line graph C. pedigree chart D. computer model 6
6. A trait is A. only a body part. B. a body part or a behavior. C. only a behavior. D. a species. 7. Clouds form when water A. evaporates B. freezes C. precipitates D. condenses 8. Which causes rocks to break down by chemical means? A. evaporation B. acid rain C. erosion D. gravity 9. Which of the following is true about the sun? A. The pull of its gravity keeps the other objects in the solar system moving around it. B. It gives off heat but no light of its own. C. The pull of its gravity keeps it moving around the other objects in the solar system. D. It is similar in size to Earth. 10. A globe is a A. two-dimensional model. B. three-dimensional model. C. symbol. D. computer model. 7
11. Engineers design racecars with as little mass as possible. Why is it important for a racecar to have so little mass? A. Cars with less mass are less likely to crash. B. A car with less mass exerts more force when hit. C. A car with less mass accelerates faster. D. Lighter cars are less expensive to build. 12. Which of the following is the energy of motion? A. electrical energy B. thermal energy C. kinetic energy D. potential energy 13. We have changing seasons because, as Earth revolves, A. the pull of the sun and moon s gravity on Earth changes. B. the length of Earth s year changes. C. Earth s distance from the sun changes. D. the amount of sunlight that different parts of Earth get changes. 14. How long does it take for Earth to make one full turn on its axis? A. 12 hours B. 27 days C. 24 hours D. 365 days 15. An adaptation A. has no use. B. helps an organism survive in its environment. C. endangers an organism in its environment. D. makes an organism extinct. 8
16. Which of the following is the symbol for an element? A. CO 2 B. CH 4 C. C D. H 2 O 17. What is a gene? A. a physical characteristic of an organism B. a diagram that shows which family members have a certain trait C. a part of DNA that carries the instructions for a trait D. an illness passed to children from their parents 18. A fault is A. a line of volcanoes. B. a crack in Earth s surface. C. where two tectonic plates meet. D. where Earth s mantle and crust meet. 19. What is scale? A. a tool used to find an object s size B. an equation used to make a model smaller C. a picture, letter, or pattern that stands for something D. the proportion between two sets of measurements 20. Newton s first law of motion states that A. a moving object continues to move at a constant velocity unless balanced forces act on it. B. an object at rest remains at rest. C. an object s acceleration depends on its mass and the force acting on it. D. an object at rest will eventually stop. 9
21. A compound is made up of A. oxygen and carbon. B. a metal and a nonmetal. C. atoms of the same element. D. two or more elements. 24. An extinct organism is A. gone forever from Earth. B. temporarily gone from Earth. C. never gone from Earth. D. adapted to its environment. 22. As a raindrop falls to the ground, its A. thermal energy decreases. B. potential energy increases. C. kinetic energy decreases. D. potential energy decreases. 25. As elevation increases, temperature tends to A. rise rapidly. B. stay the same. C. increase. D. decrease. 23. Which of the following is true of dominant traits? A. They always show up in offspring. B. They never show up in offspring. C. They get hidden by recessive traits. D. They hide recessive traits. 10
Use the picture below to answer questions 26 and 27. 28. An example of a model that uses symbols is A. a diorama. B. an equation. C. a plastic model of a heart. D. a foam ball that represents the moon. 26. Which type of plate boundary is shown? A. divergent boundary B. drifting boundary C. transform boundary D. convergent boundary 29. Information gathered with your senses is called A. a hypothesis. B. a scientific investigation. C. an inference. D. an observation. 27. Which of the following is MOST LIKELY to happen at the boundary shown? A. mountains forming B. mid-ocean ridges forming C. earthquakes shaking the ground D. volcanoes erupting 11