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End-of-Grade 8 (EOG8) Science

Last updated 6 months ago
44 questions
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Paula discovered three sedimentary rock layers that contain fossils of a lizard species. The list below shows how Paula described the lizards’ appearance in each layer.
  • Top layer: The lizards had thick tails that were about 1 inch in length.
  • Middle layer: The lizards had round tails that were about 2 inches in length.
  • Bottom layer: The lizards had flexible tails that were about 3 inches in length.
Which conclusion do Paula’s findings best support?

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How do plants contribute to the water cycle?

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What happens to water at the ocean’s surface as it moves from the equator toward the Arctic Ocean?

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The list below describes the characteristics of the forelimbs of an American toad and a bottlenose dolphin.
  • Each of the toad’s forelimbs has four fingers. The toad uses its forelimbs to grasp objects and walk.
  • The dolphin’s forelimbs are flippers with no fingers. The dolphin uses its flippers to change direction as it moves through water.
  • Both the toad’s and dolphin’s forelimbs contain bones that have many structural similarities.
Which conclusion does this information best support?

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How can people be good stewards of water resources?

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How is geothermal energy classified?

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Permafrost is created when the water in the ground freezes and remains frozen year-round. Alaska has permafrost that has remained frozen for at least 12,000 years. Scientists have discovered that this permafrost contains powerful greenhouse gases, and the permafrost releases these gases to the atmosphere as it melts. What relationship might exist between global climate change and this permafrost?

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A community uses a hydroelectric dam to generate electricity. The dam’s reservoir also flows into a water treatment plant to make the water suitable for human consumption. Suppose a drought were to occur in this community. What benefit would there be in conserving the water people use in their homes?

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How are viruses similar to parasites?

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The food web below represents the interactions of organisms P through U.


Select the two food sources for organism U.

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Which choice describes a biotic factor in an ecosystem?

Questions 12–16 are part of an item set. Use the following information to answer the questions.

Timber Falls

One summer, Jody visits Timber Falls, a waterfall along the Timber River. Jody notices a cave behind the waterfall. She wonders what forces caused this cave to form.

Jody finds an illustration (Figure 1) showing the sedimentary rock layers in this region.


Jody learns about the composition of each rock type. She ranks the hardness of each rock type on a scale of 1 to 3, where 1 is the softest rock, and 3 is the hardest. The chemical composition and relative hardness of each rock type are shown below in Figure 2.


At the Timber Falls visitor center, Jody learns trilobite fossils can be found in the shale rock layer. Trilobites are extinct invertebrate organisms that lived in the ocean. On display is a fossil of the trilobite species Dalmanites limulurus. Members of the genus Dalmanites existed on Earth between 450 and 415 million years ago.
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Jody learns that water moving over the falls formed the cave. Which choice best explains how the cave formed?

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Jody notices a fossil of a dinosaur, Stegosaurus, discovered in the dolostone layer of Timber Falls. What can Jody conclude about when Dalmanites and Stegosaurus lived?

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Jody finds a rock at the bottom of the falls. She suspects that this rock originated from the rock layers at Timber Falls. What evidence could show what type of rock she has found?

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Jody claims that moving water at Timber Falls caused the shale layer to weather. What evidence could be used to support her claim?

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Select two factors that explain why limestone weathers faster than dolostone:

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The diagram below shows a food web.


Place (click and drag) one option into the drop areas to identify the roles of the zebra, giraffe, and lion. Fill in all of the cells. Options may be used more than once.

zebra: _____________________
giraffe: _____________________
lion: _______________________
Other Answer Choices:
secondary consumer
producer
primary consumer
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Which situation is most likely to prevent a viral epidemic from becoming a pandemic?

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The diagram below shows a food web for a forest ecosystem.


A scientist introduces a population of wolves into this ecosystem. The wolves have been observed to only prey on deer. What effect would the introduction of wolves have on this ecosystem?

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Which information can best help scientists determine if two different organisms are members of the same species?

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The marine iguana is a swimming lizard that only exists on the Galapagos Islands. A species of land iguana also exists on the Galapagos Islands and other places on Earth. Scientists think that the marine iguana and the land iguana share a common ancestor. Today, most of the marine iguana’s diet is algae collected from the ocean floor. The land iguana mostly eats plants on dry land. The ancestors of the marine iguana likely spent more and more time eating algae in the ocean until the population inherited traits that made them better swimmers than land iguanas.

Which choice best summarizes this information?

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A student pours a cloudy liquid through a thin piece of paper and into a beaker. The student observes the collected liquid is not cloudy. How should the student classify the original cloudy liquid?

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Wendy draws this model to represent a neutral beryllium (Be) atom.


Wendy’s teacher says there is an error in her model. What is the error?

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How are the properties of helium (He) and krypton (Kr) similar?

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A scientist experiments on a piece of solid copper.
  • The scientist heats the copper piece and observes the copper’s density decreases as its temperature increases.
  • The scientist continues to heat the copper until it melts.
How are the decrease in density and the melting similar?

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Terry is learning about chemical reactions in science class. Terry's teacher draws this equation on the chalkboard, and explains that the equation uses a triangle, a circle, and a square as symbols to represent elements. Each symbol represents a different element.


Terry claims the equation demonstrates the law of conservation of mass. What evidence supports Terry's claim?

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Jonathan lives in a town near an estuary. The estuary is a part of the Windy River basin. The table below shows average and 2018 monthly rainfall amounts from June to September for Jonathan’s town.


Select two claims supported by this scenario.

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Each column of this table displays the properties of an element. Place (click and drag) each element into its correct position in the top row of the table. Fill in all of the cells.
Other Answer Choices:
lithium (Li)
argon (Ar)
fluorine (F)
Questions 29–33 are part of an item set. Use the following information to answer the questions.

Calm Lake Investigation

Xavier lives near Calm Lake. One summer, he notices the lake appears darker than it has in the past. Xavier finds a news article claiming that nutrient pollution has caused the change in the water’s color.

Xavier wants to learn more about nutrient pollution. He finds a diagram on the U.S. Geological Survey’s website that shows how phosphorus (P) and nitrogen (N) contribute to nutrient pollution. Figure 1 shows the diagram.



Xavier wonders how nutrient pollution may have changed the water quality. He contacts a scientist who has been studying algae in Calm Lake. The scientist explains that the algae are photosynthetic. The list below describes how the scientist measures the algae content in the lake.
  • He collects a 1-liter water sample from the lake.
  • He filters the algae from the water.
  • He removes the chlorophyll contained in each alga cell using a chemical.
To help Xavier in his investigation, the scientist provides him with two sets of measurements taken from Calm Lake over the past 30 days: the chlorophyll content and dissolved oxygen content. Figure 2 and Figure 3 show the two sets of measurements.




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Xavier learns that aquatic bacteria decrease the lake's dissolved oxygen content as they grow and reproduce. How could Xavier revise Figure 1 to better represent an effect of an increase in aquatic bacteria?

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Under normal conditions, how do the algae in Calm Lake contribute to the cycling of matter?

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Which choice best describes the amount of nutrient pollution in Calm Lake from Day 25 to Day 30?

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Use Figure 2 and Figure 3 to answer this question:

What does the change from Day 9 to Day 10 indicate?

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A fish population lives in Calm Lake. The lake water is considered unsafe for these fish if the dissolved oxygen content drops below 6 milligrams per liter of water. What does Figure 3 show about the safety of Calm Lake for these fish?

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Scientists used atmospheric temperature data from 1901 to 2000 and determined that the average global temperature, over both land and ocean, in the month of April was 13.7°C. To measure changes in climate, scientists compare a year's average April temperature to 13.7°C. The graph below is a collection of these measurements from 1960 to 2023. In the graph, a positive temperature measurement indicates that April of that year was warmer than 13.7°C. A negative measurement indicates it was colder than 13.7°C.


Which choice is the best interpretation of the graph?

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A person has recently started riding a bike to work instead of driving a gasoline-powered car. How will this action affect the availability of fossil fuels?

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An infection causes serious illness in one of four people who contract it. Scientists do not recognize the pathogen and have no way to treat it. Smaller than a cell, the pathogen is spread through air. It forces a cell to create many copies of the original pathogen and destroys the cell in the process. What is the cause of this disease, and what could scientists do to protect public health?

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Residents in a neighborhood complain that there are too many snakes in the neighborhood. A pest-control company says it can eliminate the snakes from the neighborhood. The food chain below shows how snakes participate in this ecosystem.

plants → beetle → snake → hawk

How would eliminating snakes affect this ecosystem?

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The diagram below represents a region's food chain.

plants - squirrel → coyote

Which change would increase the amount of carbon available to coyotes?

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The list below describes two different diseases.
  • Disease 1 causes facial swelling and nasal congestion. It is transmitted when an animal breathes in spores released from decaying organic matter in the environment. The pathogen that causes this disease is eukaryotic, multicellular, and can reproduce sexually and asexually.
  • Disease 2 causes itchy bumps on an animal’s skin. It is transmitted to animals through physical contact. The pathogen that causes this disease is a nonliving particle and requires a host cell to reproduce.
Select (click and drag) the choices to classify the pathogen that causes each disease. Fill in all of the cells. Options may be used more than once.

Disease 1 pathogen: ____________ Disease 2 pathogen: __________
Other Answer Choices:
bacterium
virus
parasite
fungus
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Methane is a pure substance and exists as a gas at room temperature. Each methane molecule is made up of one carbon atom chemically bonded to four hydrogen atoms. How is methane classified?

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An unidentified pure solid is composed of an element. The substance is metallic and reacts vigorously when placed in water. Where is this element most likely found on the periodic table?

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The list below describes the process of inflating a hot-air balloon.
  • A flame heats the air near the bottom opening of the deflated balloon. The air expands and rises as a result of the heating.
  • The hot air expands inside the deflated balloon. Then, the hot air applies pressure on the balloon’s fabric walls, causing the balloon to change shape.
How does the air expanding compare to the balloon changing shape?

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Suppose a large coal reserve is discovered on a mountaintop. The coal is extracted using a strip mine, where
  • the topsoil is removed by large trucks and
  • rocks are cleared by blasting with dynamite.
A town exists at the foot of the mountain.

How will this strip mine affect the environment?

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Olivia finds two dinosaur fossils in a museum:
  • Apatosaurus fossil: 150 million years old
  • Diplodocus fossil: 154 million years old
What evidence would show these organisms share a common ancestor?