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  • Science
  • Grade 9
  • Science concepts--interdependence within environmental systems

BIO.13.A

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The student is expected to investigate and evaluate how ecological relationships, including predation, parasitism, commensalism, mutualism, and competition, influence ecosystem stability;

A student expectation is directly related to the knowledge and skills statement, is more specific about how students demonstrate their learning, and always begins with a verb. Student expectations are further broken down into their component parts, often referred to as “breakouts.”

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BIO.13.A — Vertical Alignment

Vertical alignment shows student expectations in the same subject area at different grade levels that are related to or build upon one another.

Previous grade
S.3.12.C

describe how natural changes to the environment such as floods and droughts cause some organisms to thrive and others to perish or move to new locations; and

S.6.13.C
describe how variations within a population can be an advantage or disadvantage to the survival of a population as environments change.
S.8.11.C
describe the carbon cycle.
S.8.12.B
describe how primary and secondary ecological succession affect populations and species diversity after ecosystems are disrupted by natural events or human activity; and
S.8.12.C
describe how biodiversity contributes to the stability and sustainability of an ecosystem and the health of the organisms within the ecosystem.
BIO.13.A
investigate and evaluate how ecological relationships, including predation, parasitism, commensalism, mutualism, and competition, influence ecosystem stability;
BIO.13.C
explain the significance of the carbon and nitrogen cycles to ecosystem stability and analyze the consequences of disrupting these cycles; and
BIO.13.D
explain how environmental change, including change due to human activity, affects biodiversity and analyze how changes in biodiversity impact ecosystem stability.
AQUA.9.A
identify the role of carbon, nitrogen, water, and nutrient cycles in an aquatic environment, including upwellings and turnovers;
ENVIR.6.D
identify how changes in limiting resources such as water, food, and energy affect local ecosystems;
ENVIR.8.A
compare exponential and logistical population growth using graphical representations;
ENVIR.8.B
identify factors that may alter carrying capacity such as disease; natural disaster; available food, water, and livable space; habitat fragmentation; and periodic changes in weather;
ENVIR.8.C
calculate changes in population size in ecosystems; and
ENVIR.9.A
analyze and describe how natural events such as tectonic movement, volcanic events, fires, tornadoes, hurricanes, flooding, and tsunamis affect natural populations;
ENVIR.9.C
examine how natural processes such as succession and feedback loops can restore habitats and ecosystems;
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