7th grade science practice Tuesday

A scientist is studying two different biomes: a desert and a rainforest. She notices that the desert has fewer plant and animal species than the rainforest. Using your understanding of ecosystems and biomes, what is the most likely reason for this difference in biodiversity?

• The desert has more rainfall, which limits species diversity.

• The rainforest has more stable temperatures and greater availability of water, supporting more species.

• The desert has richer soil, which supports fewer plants.

• The rainforest has less sunlight, which increases biodiversity.

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NGSS.MS-LS2-1

NGSS.MS-LS2-2

A student is designing an experiment to test how the removal of a top predator affects the population sizes of other organisms in an ecosystem. Which of the following best describes a logical prediction the student could make based on ecosystem dynamics?

• The population of producers will immediately decrease.

• The population of herbivores will increase, leading to a decrease in producers.

• The population of decomposers will increase, causing more plant growth.

• The population of herbivores will decrease, leading to more predators.

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NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-3

NGSS.MS-LS2-4

A patient is experiencing difficulty breathing and poor oxygen circulation. Using your knowledge of human body systems, which two systems are most likely involved, and how do they interact to solve this problem?

• Digestive and nervous; they break down food for energy.

• Respiratory and circulatory; they work together to deliver oxygen to cells.

• Muscular and skeletal; they help the patient move.

• Excretory and immune; they remove waste and fight infection.

A doctor is planning a treatment for a patient with a malfunctioning pancreas. Which reasoning best explains how this could affect the patient’s overall health?

• The patient will have trouble digesting proteins only.

• The patient may have difficulty regulating blood sugar, affecting energy levels throughout the body.

• The patient will be unable to absorb water in the large intestine.

• The patient will have increased bone density.

Tags

NGSS.HS-LS1-3

A student mixes two clear solutions in a beaker and observes the formation of a solid and a temperature change. Which reasoning best explains what type of chemical reaction has occurred?

• A physical change, because the substances are still the same.

• A chemical reaction, because new substances with different properties formed.

• A phase change, because the temperature changed.

• A mixture, because two substances were combined.

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

A car is moving at a constant speed on a straight road. Suddenly, the driver applies the brakes, and the car comes to a stop. Using your understanding of forces and motion, which reasoning best explains what causes the car to stop?

• The car stops because gravity pulls it down.

• The car stops because friction between the brakes and wheels creates an unbalanced force opposite to the motion.

• The car stops because the engine turns off.

• The car stops because air resistance increases.

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NGSS.MS-PS2-2

A student is designing a roller coaster and wants to maximize the speed at the bottom of the first hill. Which reasoning best explains how the height of the hill affects the speed at the bottom?

• The higher the hill, the more potential energy is converted to kinetic energy, increasing speed.

• The lower the hill, the more friction slows the coaster.

• The height does not affect the speed at all.

• The higher the hill, the less energy is available for motion.

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NGSS.MS-PS3-1

NGSS.MS-PS3-5

A geologist is studying the movement of tectonic plates. She observes that earthquakes often occur at plate boundaries. Using your knowledge of Earth's layers, which reasoning best explains why this happens?

• The mantle is solid and does not move.

• The plates float on the semi-fluid asthenosphere, and their movement causes stress and earthquakes at boundaries.

• The core is responsible for all earthquakes.

• The crust is too thick for movement.

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NGSS.MS-ESS2-3

NGSS.MS-ESS3-2

A student is asked to explain how volcanic eruptions are related to the structure of the Earth. Which reasoning best connects volcanic activity to Earth's layers?

• Volcanic eruptions occur because the crust is made of metal.

• Volcanic eruptions happen when magma from the mantle rises through weaknesses in the crust.

• Volcanic eruptions are caused by the movement of the inner core.

• Volcanic eruptions only occur in the ocean.

A meteorologist is comparing two cities: one near the ocean and one far inland. Both cities are at the same latitude. Using your understanding of weather and climate, which reasoning best explains why the coastal city has milder temperatures year-round?

• The ocean absorbs and releases heat more slowly than land, moderating the temperature.

• The inland city receives more sunlight.

• The coastal city is at a higher altitude.

• The inland city has more clouds.

Tags

NGSS.MS-ESS2-6