Food Chains, Webs and Pyramids

A student is asked to draw a food web in which the same organism is a primary consumer as well as a secondary consumer. How should the organism be represented in the food web?

• The organism must have an arrow pointing from it to a tertiary consumer and another arrow pointing from it to a decomposer.

• The organism must have an arrow pointing from it to a secondary consumer and another arrow pointing to it from the top predator.

• The organism must have an arrow pointing from it to a primary consumer and another arrow pointing away from it to a decomposer.

• The organism must have an arrow pointing to it from a producer and another arrow pointing to it from a primary consumer.

The amount of energy the producers in this energy pyramid provide the primary consumers is 54,000 joules. From this amount, 540 joules are provided to the tertiary consumers. Based on this model, how much of the energy was provided to secondary consumers?

• 5,400 J

• 53,460 J

• 54 J

• 540 J

Tags

NGSS.MS-LS2-3

Which of the following organisms can be both a secondary and a tertiary consumer?

• Lizard and small reptiles

• badgers

• ground squirrels

• mountain lion

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NGSS.MS-LS2-2

Part of a hydrothermal vent food web is represented in the diagram. Which organisms are both secondary and tertiary consumers in this food web?

• Zooplankton and mussels

• Chemosynthetic bacteria and amphipods

• Galatheid crabs and zoarcid fish

• Ratfish and octopuses

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NGSS.MS-LS2-2

Which of the following are missing from the food web shown above?

• omnivores

• predators

• producers

• decomposers

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NGSS.MS-LS2-2

NGSS.MS-LS2-3

An ocean food chain is shown in the diagram above. Which organism represents the trophic level containing approximately 1% of the initial amount of solar energy acquired by the phytoplankton?

• sand eels

• herring

• humans

• copepods

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NGSS.MS-LS2-3

The food web shows the flow of energy through a sagebrush-steppe ecosystem. Which of these organisms are in a trophic level that receives a larger percentage of the energy captured by the producers than the percentage received at the snakes’ trophic level?

• coyotes

• bats

• insects

• hawks

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NGSS.MS-LS2-1

NGSS.MS-LS2-3

In recent years humans have interfered with the natural balance within deer populations in various ecosystems. The interference includes eliminating predators of the deer. Which of the following statements correctly describes the long-term outcome of this interference?

• Other browsing species will thrive and out compete the deer

• The producers will evolve into species that are less palatable to the deer

• The deer that are the fastest and most agile will survive and reproduce.

• The deer population will be too large to be supported by producers

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NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Food webs such as the one shown were first used in 1927 by the animal ecologist Charles Elton. The food web below represents the feeding relationships among different organisms. An environmental change that removed which of these organisms from the ecosystem would cause the most instability in the ecosystem?

• foxes

• zooplankton

• salmon

• auklets

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

A marine ecosystem is represented in the picture. What is lost to the environment at each of the trophic levels of this ecosystem?

• living space for the organisms

• nutrients from the soil

• food sources

• heat

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3