Unit 2 — Matter and Energy in Organisms and Ecosystems
Description
Students analyze and interpret data, develop models, construct arguments, and demonstrate a deeper understanding of the cycling of matter, the flow of energy, and resources in ecosystems. They study patterns of interactions among organisms within an ecosystem, considering biotic and abiotic factors and their effects on populations. They understand that limits of resources influence the growth of organisms and populations, which may result in competition for limited resources.
Essential Questions
- How and why do organisms interact with their environment and what are the effects of these interactions?
- How do changes in the availability of matter and energy affect populations in an ecosystem?
- How do relationships among organisms in an ecosystem affect populations?
- How can you explain the stability of an ecosystem by tracing the flow of matter and energy?
Learning Objectives
- Analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations
- Construct an explanation that predicts patterns of interactions among organisms across multiple ecosystems
- Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem
- Use cause-and-effect relationships to predict effects of resource availability
- Recognize patterns showing competition for limited resources
- Understand food webs and energy transfer in ecosystems
Supplemental Resources
- Graphic organizers for food webs and energy cycle diagrams
- Data tables and charts for recording ecosystem observations and measurements
- Printed cards showing organisms for food web construction activities
- Construction paper for creating visual models of ecosystems and food chains
- Markers and colored pencils for developing ecosystem diagrams and illustrations
Engineering, Technology, and Applications of Science
Life Sciences
Students cite textual evidence from science and technical texts, write arguments and informative/explanatory texts focused on discipline-specific content, gather and evaluate information from multiple sources, and draw evidence from informational texts to support analysis and research across all units. Reading standards for science and technical texts (RST.6-8.1, RST.6-8.2, RST.6-8.7, RST.6-8.8, RST.6-8.9) and writing standards (WHST.6-8.1, WHST.6-8.2, WHST.6-8.7, WHST.6-8.8, WHST.6-8.9) are explicitly referenced throughout all units. Speaking and listening standards support collaborative discussions and multimedia presentations.
Students use ratio and rate reasoning, summarize numerical data sets, represent relationships between variables using graphs and equations, and apply mathematical practices including reasoning abstractly and modeling with mathematics. Mathematical standards 6.SP.A.2, 6.SP.B.4, 6.SP.B.5, 6.EE.C.9, 6.RP.A.3, and Standards for Mathematical Practice MP.2 and MP.4 are explicitly referenced across units to support data analysis, statistical reasoning, and quantitative thinking in science contexts.
Formative Assessments
- Students analyze and interpret data on resource availability and population effects
- Students construct explanations about ecosystem interactions and relationships
- Students make predictions about competitive, predatory, and mutually beneficial interactions
- Students develop models of food webs and energy flow
- Students observe and measure patterns of objects and events in ecosystems
Summative Assessment
Quiz (25 multiple choice/5 true-false questions), Test (45 MC/True-False questions), Ecosystem Simulation Project, Lab Reports
Benchmark Assessment
— not configured —
Alternative Assessment
Students may demonstrate understanding through a series of labeled diagrams with teacher-guided oral explanations in place of written responses, or by sorting and matching cards showing organisms, resources, and ecosystem interactions. Word banks, partially completed concept maps, and visual models of energy flow may be provided as scaffolds.
IEP (Individualized Education Program)
For this unit's focus on matter cycling, energy flow, and ecosystem interactions, students may benefit from graphic organizers that visually map relationships between biotic and abiotic factors, food webs, and cause-and-effect chains. Providing pre-labeled diagram templates for modeling tasks and allowing oral or drawn responses in place of written explanations can reduce barriers to demonstrating conceptual understanding. Extended time on quizzes and tests, chunked directions for lab reports and simulation tasks, and highlighted or simplified text for data analysis passages will support processing and output. Vocabulary support with visual anchors for key terms such as producer, consumer, decomposer, and limiting resource should be introduced before instruction and revisited throughout the unit.
Section 504
Students should be given extended time on the unit quiz, test, and any data analysis tasks involving multi-step interpretation. Preferential seating during class discussions and lab activities will support focus, particularly when students are observing patterns in ecosystem scenarios or participating in simulation activities. Printed copies of any diagrams, data sets, or directions displayed on the board will ensure consistent access to unit content throughout the 25-day pacing.
ELL / MLL
Key vocabulary related to ecosystems — such as organism, population, competition, predator, energy transfer, and resource availability — should be introduced with visual supports such as diagrams, labeled photographs, and word walls before and during instruction. Directions for data analysis tasks and lab reports should be simplified and paired with visual models of expected formats so students understand what is being asked before they begin. Where possible, connecting ecosystem concepts to environments familiar to students' home regions or cultures can build meaningful background knowledge and lower the affective barrier to engagement with new content.
At Risk (RTI)
Connecting new content to students' prior experiences with living things, weather, food, and local environments can serve as a strong entry point into the abstract concepts of matter cycling and energy flow. Simplifying the complexity of food web models to begin with two or three organisms before expanding, and focusing initial data interpretation tasks on one variable at a time, will help students build confidence and conceptual footing. Frequent check-ins during lab and simulation work, along with structured note-taking frames that guide students through key relationships without overwhelming them, will help maintain momentum and support mastery of core ideas.
Gifted & Talented
Students who demonstrate early mastery of food web structure and energy transfer can be challenged to examine multi-layered ecosystem disruptions, such as the cascading effects of removing a keystone species or introducing an invasive competitor, requiring analysis across multiple trophic levels. Encouraging students to critique or revise existing models of matter cycling by identifying their limitations — what they cannot show or predict — pushes toward the kind of abstract, higher-order thinking appropriate for this population. Independent or small-group research into real-world ecosystem case studies, evaluated through student-designed models or written arguments, offers depth and authentic scientific reasoning beyond the core unit scope.