Study Island. Generation Date: 04/03/2014 Generated By: Cheryl Shelton Title: Grade 8 Life & Physical Science

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1 Study Island Copyright 2014 Edmentum - All rights reserved. Generation Date: 04/03/2014 Generated By: Cheryl Shelton Title: Grade 8 Life & Physical Science 1. When lettuce and some other vegetables spoil, they become black and slimy. What type of chemical change makes the vegetables spoil? A. Fast oxidation burns the vegetables to make ash. Bacteria digest the vegetables and produce waste. Slow oxidation causes the vegetables to rust. The vegetables react with acidic compounds in the air. 2. Chemical changes create new types of matter. Oxidation is the name for the chemical change that happens when a substance reacts with oxygen. Which of the following is an example of slow oxidation? A. A raw steak goes bad and turns green. Rust forms on an iron shovel left outdoors. A log burns in a fire place and becomes ash. Bubbles form from vinegar and baking soda. 3. Which of the following has the ability to turn light energy into chemical energy? A. an automobile water a tree a book 4. Which of the following best describes how a species changes over time? A. Members of a species that are best adapted to survive and members with unfavorable traits

2 both produce the same number of offspring. Diversity among members of the species causes all members to stop producing offspring. Members of a species that are best adapted to survive produce offspring with similar characteristics, while members with unfavorable traits do not survive. Members of a species with unfavorable traits produce offspring with similar characteristics, while members best adapted to survive do not reproduce. 5. Gills are respiratory organs that allow oxygen to be absorbed from. A. food water salt air 6. In a cell, what is the function of the vacuole? It removes waste, stores ingested food and provides cellular structure. A. It is where photosynthesis occurs. It controls the entry and exit of substances. It generates energy for the cell, removes waste and provides cellular structure. 7. All living organisms are composed of A. at least 100 cells. at least three cells. only one cell. one or more cells. 8. Lance is rubbing two sticks together. The friction causes the kinetic energy from rubbing the two sticks to be converted into

3 A. chemical energy. potential energy. electrical energy. heat energy. 9. The development of a structure containing many sensory tissues and organs was a major evolutionary development in animals. This structure faces the direction in which the organism moves, allowing the organism to sense the environment before moving toward it. What is the structure developed to help organisms sense their surroundings? A. skin limb tail head 10. Due to its ability to camouflage itself from predators, the White Peppered Moth of England was once much more abundant than the Black Peppered Moth. As the Industrial Revolution hit, factories began to release black soot which coated everything, including tree bark. Because the moths habitat was now darker, the white moth became much more susceptible to predators. At the same time, the Black Peppered Moth was now more protected and began to increase in number. This story is an example of A. extinction. natural selection. mutation. endangered species. 11. In a population of lizards, 25 percent have dark coloring and 75 percent have light coloring. Over time, the environment where the lizards live becomes forested. The dark lizards can hide more easily than the light lizards because they blend in with the tree trunks. The lizard population changes into 80 percent dark-colored lizards and 20 percent light-colored lizards. What is this an example of? A. disruptive selection natural selection

4 genetic mutation genetic drift 12. The cell membrane A. alters and packages proteins and lipids. controls which substances enter and exit the cell. is the site of most cellular chemical reactions. converts glucose to other energy molecules. 13. Copper is added to a solution of nitric acid. The solution becomes hot and changes from colorless to dark blue. What is the best explanation for the change in temperature? A. The blue color absorbs less energy, which causes heat to be released. The copper and nitric acid repel each other, which produces heat. The chemical reaction between the copper and the nitric acid produces heat. The increased volume of the solution causes heat to be released. 14. Hank has a very detailed model of the solar system where each planet is made out of granite rock. Since his little sister really liked the model, he spent two weeks in his dad's workshop building her a Styrofoam copy. When he picked up the models to take them back inside the house, which physical property would he immediately notice upon picking them up? A. conductivity ductility density color 15. Density refers to a physical property that is measured using a ratio of divided by so that two objects of the same size can still have very different density. A. weight, height concentration, mass mass, volume height, width

5 16. Which of the following items would have the lowest density? A. A 6 cm 3 block of ice with a mass of 4 grams A 12 cm 3 block of aluminum with a mass of 2 grams A 12 cm 3 block of wood with a mass of 3 grams A 2 cm 3 block of lead with a mass of 11 grams 17. Hunter found some termites in a wooden board sitting in his backyard, so he sprayed some insecticide on the board to kill the termites. Hunter noticed that about 95% of the termites died, but 5% survived. What is the most likely explanation for this? A. The living termites knew that Hunter was going to spray the insecticide, so they camouflaged themselves. The living termites had genes that the dead termites did not have. The living termites were males and the dead termites were females. The living termites were a different species than the dead termites. 18. Which of the following situations describes an object's kinetic energy being converted into gravitational potential energy? A kiwi is dropped from a second-story window. A. A water particle flows down a mountain stream. A penny sits motionless atop a shelf. A ball rolls up an inclined ramp. 19. Four liquids were poured on top of each other in a glass, and the liquids separated into four different layers. Which liquid had the lowest density? A. the layer at the top of the glass the third layer from the bottom of the glass

6 the second layer from the bottom of the glass the layer at the bottom of the glass 20. Which of the following organisms has an exterior that is radially symmetric? A. a snake a cat an ant a starfish