Exploring Biogeochemical Cycles

What is the primary source of energy for most food webs on Earth?

• The Moon

• The Sun

• Wind

• Soil

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NGSS.MS-LS1-6

NGSS.MS-LS2-3

Which of the following best describes a trophic level?

• The number of organisms in an ecosystem

• The position an organism occupies in a food chain

• The amount of sunlight an ecosystem receives

• The rate at which plants grow

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NGSS.MS-LS2-3

Which process in the carbon cycle involves plants taking in carbon dioxide from the atmosphere?

• Respiration

• Photosynthesis

• Decomposition

• Combustion

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NGSS.MS-LS1-6

Which of the following is an example of a food chain?

• Grass → Grasshopper → Frog → Snake

• Grass, Trees, Flowers

• Snake, Frog, Grasshopper, Grass

• Sun → Water → Soil

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NGSS.MS-LS2-3

If a pesticide is introduced at the producer level in a food web, which trophic level is likely to be most affected by biomagnification?

• Producers

• Primary consumers

• Secondary consumers

• Tertiary consumers

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NGSS.MS-LS2-4

A decrease in net primary productivity in an ecosystem would most likely result in:

• An increase in biodiversity

• A decrease in the amount of energy available to higher trophic levels

• More producers

• An increase in nitrogen in the soil

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

Given a simple food web: Grass → Rabbit → Fox. If the rabbit population decreases significantly, what is the most likely effect on the fox population? Explain your reasoning.

• The fox population will increase due to more food.

• The fox population will decrease due to less food.

• The fox population will remain the same.

• The fox population will become producers.

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NGSS.MS-LS2-1

NGSS.MS-LS2-4

A farmer adds large amounts of phosphorus-rich fertilizer to a field. Predict and explain one possible impact this could have on a nearby aquatic ecosystem.

• Increased biodiversity due to more nutrients

• Decreased oxygen levels due to algal blooms

• No effect, as phosphorus does not move into water

• Decreased plant growth in the field

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NGSS.MS-LS2-1

NGSS.MS-LS2-4

What is the formula for calculating Net primary productivity in an ecosystem?

• NPP = GPP - Respiration

• NPP = GPP + Respiration

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NGSS.HS-LS1-5

NGSS.HS-LS2-5

Why are there fewer predators than prey in an ecosystem?

• Because energy decreases by 90% at each trophic level.

• Because energy decreases by 10% at each trophic level.

Tags

NGSS.MS-LS2-3