Study Island Copyright 2014 Edmentum - All rights reserved. Generation Date: 04/03/2014 Generated By: Cheryl Shelton Title: Grade 7 Life & Physical Science 1. Decomposers are organisms that A. feed upon living organisms. B. use sunlight to produce food. C. can only be seen using a microscope. D. break down matter from dead plants and animals. 2. Which of the following is true about the mass of the reactants in a chemical reaction? A. B. C. D. The total mass of the reactants in a chemical reaction will be significantly more than the total mass of the products. The total mass of the reactants in a chemical reaction will be significantly less than the total mass of the products. The total mass of the reactants in a chemical reaction will never be equal to the total mass of the products. The total mass of the reactants in a chemical reaction is conserved and will be equal to the total original mass of the products. 3. Which of the following organisms is an invertebrate? A. snake B. fish C. snail D. salamander
4. An organism that feeds upon primary consumers is known as a. A. host B. secondary consumer C. decomposer D. producer 5. In terms of ecological succession, an undisturbed community tends to become over time. A. less diverse B. less stable C. less complex D. more stable 6. Animals have a great variety of internal structures that define the way they live. For example, a bear has lungs to help it get oxygen to all of its cells. What does a fish have that serves the same function? A. fins B. lungs C. scales D. gills 7. Snakes hunt and kill small rodents as a food source. This is an example of. A. commensalism B. mutualism C. neutralism D. predation 8. In a closed system, the total energy prior to an energy transformation is the total energy after. A. equal to
B. greater than C. unrelated to D. less than 9. Eddie has a container of water. The water in the container has a mass of 25 grams. He places the container in the freezer and the water freezes. Which of the following is true? A. The mass of the ice is less than 25 grams. B. The mass of the ice is more than 25 grams. C. The ice has a mass of 25 grams. D. There is no way to determine the mass of the ice. 10. Marsupials, such as kangaroos and koala bears, are mammals. Humans are mammals, too. However, there are differences between marsupials and humans. For instance, the average baby human is born after spending 38-40 weeks inside of its mother, but baby marsupials are born after only 4-5 weeks. What feature does a marsupial possess that allows babies to be born earlier? A. an egg sac B. a uterus C. a pouch D. fur 11. If there were no decomposers, which of the following would most likely happen? A. Animals would start carrying out photosynthesis. B. Some plants might die due to a shortage of important nutrients. C. The amount of dead plant and animal matter would decrease. D. Plants and animals would remain living for a longer period of time. 12. In the chemical reaction below, sodium (Na) and chlorine (Cl) combine to form sodium chloride (NaCl). 2Na + Cl 2 2NaCl
If the combined mass of the starting reactants is 50 grams, then the mass of sodium chloride formed once the reaction has reached completion will be exactly 50 grams. A. will be exactly 100 grams. B. will be less than 50 grams. C. will be between 50 and 100 grams. D. 13. The Blue Ridge Mountains of Virginia are covered by hardwood forests. People in this region often use the hardwood trees to build their homes. How will this most likely affect the environment of the Blue Ridge Mountains? A. The economy of the region will drastically improve. B. The habitat size for tree-dwelling animals will decrease. C. The biodiversity of the Blue Ridge Mountains will increase. D. The tree species in the area will become extinct. 14. Which of the following events brings about the most rapid ecological change? A. drought B. succession C. forest fire D. decomposition 15. A tapeworm can attach itself to the intestinal wall of a dog and live off of the food that the dog eats. The tapeworm is a, and the dog is the tapeworm's. A. parasite; host B. producer; supplier C. carnivore; prey D. predator; prey 16. Earthworms have tiny bristles called setae which usually stay inside of their bodies. They can, however, jab them into the surrounding dirt to help them move forward. What is another way that earthworms often use their setae?
A. to help push dirt in their mouths when eating B. to anchor themselves to the ground when a bird tries to pull them away C. to glide along the surfaces of water bodies D. to help oxygen diffuse through their skin better 17. A mite is a tiny organism that may ride on top of an insect, such as a beetle, in order to move quickly from place to place. The relationship between the mite and the beetle would be an example of commensalism if the mite protects the beetle from predators. A. the beetle is neither harmed nor helped by the mite. B. the beetle is unable to catch prey because it is slowed down by the mite. C. the beetle eats the mite. D. 18. Which relationship below is an example of a predator-prey relationship? A. A rabbit eats grasses. B. A giraffe eats the leaves from tall trees. C. A coyote eats a hen. D. A pet fish eats fish food. 19. Which statement is true about energy changes? A. Energy can be created and destroyed. B. Energy can be destroyed but not created. C. Energy can be created but not destroyed. D. Energy cannot be created or destroyed. 20. An organism that feeds upon producers is known as a. A. decomposer B. primary consumer
C. secondary producer D. secondary consumer