Unit 1 & 2 Cumulative Test

1. Unit 1 & 2 CumulativeTest 6th Grade

2. Rules • Each group will be given a question to answer. • You may discuss the question between your team members and decide the correct answer • You must give a reason WHY this is the correct answer • The team with the most correct answers wins.

3. Question 1 • For the Science Fair, Alyssa designs an experiment to learn about erosion. First, she sets up three long trays with equal-sized piles of sand at one end of each tray. Then she sets up Tray A so that it lays flat on a table. She elevates the end of Tray B that holds the sand by 5 cm (centimeters). Next, she elevates the end of Tray C that holds the sand by 10 cm. Alyssa slowly pours 200 mL (milliliters) of water onto the sand in each tray. Finally, she observes and measures how far sand is carried by the water poured into each tray. What is the test variable (independent variable) in Alyssa's experiment? • A the volume of water she pours • B the speed she pours the water • C the height of the tray • D the amount of sand C is correct because the height of the tray is the variable that is being changed in each test group.

4. Question 2 • A scientist watched a desert lizard stand in the rain. It spread its legs stretching its body wide, and held its head and tail down. It opened and closed its mouth in a rhythmic way. The scientist dropped colored water on the lizard's back and watched it move through channels toward the lizard's head. The scientist thought the lizard might be using its body to catch rain water to drink. To test his idea, he captured several lizards. He then dripped rainwater on the lizards and observed that the lizards always repeated the behavior What was the scientist's hypothesis after observing the lizard in the desert? • A Lizards like water. • B Lizards can survive in the desert. • C Desert lizards use their bodies to catch rainwater to drink. • D Water can run along a lizard's back. C is correct because it is a testable statement

5. Question 3 • A scientist is unsure about the accuracy of her experiment. She has checked her equipment and found it to be in good working order, checked her data and found it to be accurate, and reviewed her interpretation of the data, which she found to be logical. What should she do in addition to check the accuracy of her results? • A check the hypothesis • B interpret the data • C make a different conclusion • D repeat the experiment D is correct because repetition helps to verify experimental results to determine if they are accurate and can be trusted

6. Question 4 • A cellular phone company tested its phones for safe levels of radiation. They repeated the test 1,000 times. Which of the following statements explains why the results can be described as repeated but not replicated? • A The company is only repeating part of the test. • B The results have not been replicated by independent researchers. • C The company repeated the test too many times to be valid. • D They company did not obtain the same results each time B is correct because although the cell phone company has repeated the test, it has not been repeated, or replicated, by independent researchers, which makes the results less acceptable

7. Question 5 • Frank wants to determine how the type of container that holds a liquid affects the evaporation rate of the liquid. Which of the following describes the best type of scientific investigation for finding the answer to this question? • A an experiment in which the size, shape or material of which a container is made is changed but all other variables are kept the same • B an experiment that varies the temperature of the liquid, but keeps all other variables the same • C systematic observations in which measurements are taken of the evaporation levels on a measuring cup full of water for several days • D causal observations of how long it takes rainwater that forms puddles in various outdoor locations to evaporate A is correct because it describes a controlled experiment that will provide a fair test for the question

8. Question 6 • In some classes, students are not supposed to discuss their work with other students. What is one reason that science lab, unlike other classes, might benefit from including discussion? • A Discussion of an investigation allows students to find errors and change data. • B Discussion of an investigation allows students to select the best data and discard the rest. • C Discussion of an investigation allows students to better understand methods and conclusions. • D Discussion of an investigation allows students to find errors and change results. C is correct because communicating results allows others to evaluate the methods used during a scientific investigation and how the data support the conclusion

9. Question 7 • As new information is discovered, scientific theories are changed. Sometimes, old theories are thrown out. Why is this a necessary condition for good science? • A It ensures that the newest ideas are the ones used to develop medicines and important safety equipment. • B The process allows for an increasingly accurate understanding of the world. • C Old theories are dependent on primitive technology that was flawed, so new technology must be used. • D New scientists need to get credit for their ideas or no one will go into science B is correct because modification or replacement of existing theories ensures that our current understanding of the world is based on all relevant information

10. Question 8 • Scientific knowledge continues to expand as new discoveries are made. Which of the following has played the most significant role in advancing scientific knowledge about cell biology? • A syringe • B pie chart • C microscope • D triple-beam balance C is correct because the microscope revealed a whole new world, in the form of microorganisms, which were invisible to the naked eye

11. Question 9 • Hannah is driving a car up a hill. She observes that the car tends to slow down if she does not press down on the accelerator. Hannah suggests that friction between the car and the road is causing the car to slow down. How would scientists characterize Hannah’s suggestion? • A a theory • B a hypothesis • C an observation • D intuition B is correct because a hypothesis is a suggested answer to a scientific question that is developed based on known information and can be tested through experimentation.

12. Question 10 • The Orion Nebula is a gaseous cloud in space containing billions of new stars. When viewing it through a high-powered telescope, an observer sees what the nebula looked like 1,500 years ago. How is this possible? • A The nebula is 1,500 years old. • B It takes 1,500 years for light from the nebula to reach Earth. • C Light from the telescope takes 1,500 years to reach the nebula. • D A high-powered telescope needs to be adjustedfor its location. B is correct because light from the stars must travel through space to reach Earth.

13. Question 11 LUCKY PICK – NO EXPLANATION REQUIRED!!! • A galaxy includes billions of different objects. Which of the following objects in our galaxy is largest? • A asteroid • B meteor • C planet • D star D is correct because a star is the largest object listed.

14. Question 12 • Jamal made a model of the universe using common objects to represent the universe, the Milky Way, the solar system, and the Sun. He used his classroom, a extra-large pizza, a tennis ball, and a grape to represent objects in his model. Which object represented the universe? • A the classroom • B the pizza • C the tennis ball • D the grape A is correct because the classroom, like the universe, is the largest object

15. Question 13 – NO Explanation – Give me a sentence instead! • The Hubble Space Telescope recently provided an image that led to the discovery of a galaxy 13.2 billion light-years from Earth. Which of the following statements about the newly discovered galaxy is most likely true? • A The galaxy is smaller than the sun. • B The galaxy is within a solar system. • C The galaxy is composed of billions of stars. • D The galaxy is smaller than a star. C is correct because galaxies are composed of billions of stars

16. Question 14 • The graph compares the surface temperature and color of stars. What would be the color of a star that has a surface temperature of 15,000 K? • A blue • B blue-white • C white • D red B is correct because the temperature of a blue-white star is about 10,000 to 25,000 K.

17. Question 15 • Eduardo looks at stars through his telescope. He says that the star Sirius is brighter than the star Rigel. In reality, Rigel has a greater absolute brightness than Sirius. What can explain Eduardo’s observation? • A Sirius is much closer to Earth than Rigel. • B Rigel is much closer to Earth than Sirius. • C Sirius is a hotter star than Rigel. • D Rigel is a hotter star than Sirius. A is correct because stars that are closer to Earth appear brighter than stars farther from Earth.

18. Question 16 • Two stars have the same apparent magnitude as seen from Earth’s surface. Star A is 33 ly away. Star B is 346 ly away. Which of the following statements is true? • A. Star B is larger than star A • B. Star B is more luminous than star A • C. The stars have the same absolute magnitude • D. Star A has a smaller absolute magnitude B is correct because apparent magnitude is how the star aPPears to be, a bright star that is further away may look the same as a dim star that is closer (its an illusion)

19. Question 17 • Which of the following statements best describes a binary star system? • A. A star appears blue in the night sky • B. A star is orbited by a gas giant planet • C. Two pairs of stars orbit each other • D. Two stars orbit each other D is correct because binary means two. C is the distractor, because two PAIRS of stars mean that there are 4 stars not 2

20. Question 18 • Which of the following units is used to express the size of stars? • A kilometer • B Light-year • C solar radius • D astronomical units D is correct because the distance from one side of the star across to the other side of the star is the radius and shows the actual size