Unit 7 CBA Review

Which statement below best describes how biodiversity contributes to the sustainability of an ecosystem?

• A variety of plant and animal species allows for more survivors of a natural disaster.

• Having more species in an ecosystem allows the human population to increase in size.

• Low biodiversity reduces the competition for resources, which helps native species survive.

• Fewer species in the ecosystem reduces the likelihood that disease spreads through the ecosystem.

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NGSS.MS-LS2-5

Students were asked to make a claim supported with evidence to answer the question, “Which ecosystem would be most sustainable if all the grasses died from severe drought?” What claim is valid and supported by the evidence?

• The forest ecosystem is most sustainable because there are more top predators.

• The grassland ecosystem is most sustainable because there are fewer organisms that eat grass.

• The forest ecosystem is most sustainable because most of the animals can eat other organisms.

• The grassland ecosystem is most sustainable because there is less competition for food.

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NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Why is biodiversity important in an ecosystem?

• The number of offspring for a species increases.

• It creates more competition for resources among species.

• The number of organisms in the food pyramid will increase at each trophic level.

• It leads to stability of an ecosystem, which enables it to withstand a disturbance.

Tags

NGSS.MS-LS2-5

The role of a pioneer species in primary succession is to change a bare habitat into one that is suitable for other organisms. A species that is responsible for primary succession in an ecosystem is most likely able to —

• survive any predator

• migrate during the winter

• live at high altitudes

• carry out photosynthesis

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NGSS.MS-LS1-6

A hurricane hits a coastal prairie and destroys the habitat. Years later there is an appearance of small plants with rapidly spreading roots.This vegetation describes —

• a microhabitat

• primary succession

• secondary succession

• biodiversity

Which event would most likely cause an ecosystem to have the lowest biodiversity and population sizes 3 years later?

• Clearing land for a highway

• A river floods a cornfield

• A forest fire destroys the plant growth

• A lava flow creates a new section of land

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NGSS.MS-LS2-1

NGSS.MS-LS2-4

When forest fires destroyed many of the pine trees in Bastrop State Park, the burned areas began secondary succession. What is the role of succession in this example?

• Creating new soil by chemical and physical weathering of rocks

• Restoring the ecosystem through grass, shrub, and tree stages

• Changing the landscape to be more fire resistant in the future

• Opening the land for new uses like farming and raising livestock

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NGSS.MS-LS2-3

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Students observe ecological succession of a field that has been left bare. Which of the following are the students likely to observe first?

• Growth of shrubs and trees

• Formation of topsoil

• A mature grassland community

• Growth of grasses and weeds

Tags

NGSS.MS-LS1-5

What is the relationship between ecological succession and equilibrium in an ecosystem?

• Ecological succession leads to equilibrium in an ecosystem.

• Ecological succession prevents ecosystems from ever reaching equilibrium.

• There is no relationship between ecological succession and equilibrium.

• Ecological succession and equilibrium are the same thing.

Which of the following sequences most likely represents ecological succession on a recently abandoned wheat field?

• grasses-flowering plants-shrubs-native trees

• native trees-shrubs-flowering plants-grasses

• shrubs-grasses-native trees- flowering plants

• flowering plants - native trees-shrubs-grasses

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NGSS.MS-LS1-5

NGSS.MS-LS2-1

NGSS.MS-LS2-4