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HS-LS2-4 (Science (CA NGSS))


Standard Identifier: HS-LS2-4
Content Area: Science (CA NGSS)
Grade Range: 9–12
Disciplinary Core Idea: LS2.B: Cycles of Matter and Energy Transfer in Ecosystems
Cross Cutting Concept: CCC-5: Energy and Matter: Flows, Cycles, and Conservation
Science & Engineering Practice: SEP-5: Using Mathematics and Computational Thinking
Content Area: Life Science

Title: HS-LS2 Ecosystems: Interactions, Energy, and Dynamics

Performance Expectation: Use mathematical representations to support claims for the cycling of matter and flow of energy among organisms in an ecosystem. [Clarification Statement: Emphasis is on using a mathematical model of stored energy in biomass to describe the transfer of energy from one trophic level to another and that matter and energy are conserved as matter cycles and energy flows through ecosystems. Emphasis is on atoms and molecules such as carbon, oxygen, hydrogen and nitrogen being conserved as they move through an ecosystem.] [Assessment Boundary: Assessment is limited to proportional reasoning to describe the cycling of matter and flow of energy.]

Disciplinary Core Idea(s):
LS2.B: Cycles of Matter and Energy Transfer in Ecosystems Plants or algae form the lowest level of the food web. At each link upward in a food web, only a small fraction of the matter consumed at the lower level is transferred upward, to produce growth and release energy in cellular respiration at the higher level. Given this inefficiency, there are generally fewer organisms at higher levels of a food web. Some matter reacts to release energy for life functions, some matter is stored in newly made structures, and much is discarded. The chemical elements that make up the molecules of organisms pass through food webs and into and out of the atmosphere and soil, and they are combined and recombined in different ways. At each link in an ecosystem, matter and energy are conserved.

Science & Engineering Practices: Using Mathematics and Computational Thinking Use mathematical representations of phenomena or design solutions to support claims.

Crosscutting Concepts: Energy and Matter Energy cannot be created or destroyed—it only moves between one place and another place, between objects and/or fields, or between systems.

California Environmental Principles and Concepts:
Principle II The long-term functioning and health of terrestrial, freshwater, coastal, and marine ecosystems are influenced by their relationships with human societies. Principle IV The exchange of matter between natural systems and human societies affects the long-term functioning of both.

California Common Core State Standards Connections:
Mathematics MP.2: Reason abstractly and quantitatively. MP.4: Model with mathematics. N-Q.1-3: Reason quantitatively and use units to solve problems.

DCI Connections:
Connections to other DCIs in this grade-band: HS.PS3.B; HS.PS3.D Articulation across grade-bands: MS.PS3.D; MS.LS1.C; MS.LS2.B

Questions: Curriculum Frameworks and Instructional Resources Division | CFIRD@cde.ca.gov | 916-319-0881