Unit 4 — LS: structure and function

• Student investigations providing evidence of cellular composition in living things through microscopic observation or laboratory data collection.
• Modeling activities where students develop and revise representations of cell structure and function.
• Observation of student ability to distinguish between living and nonliving things and to classify organisms as unicellular or multicellular.
• Student explanations of how specialized cell structures relate to cell function and how body systems interact.
• Discussions and written responses addressing essential questions about cellular needs, body systems, and organism response to stimuli.

Students conduct a short research project to answer a focused question about cell structure and function or body systems, drawing on multiple sources and generating related questions for exploration. The project demonstrates understanding of how cells and body systems are organized and function.

A task requiring students to identify cell structures in a provided image or diagram and explain one function of each structure, and to classify organisms as living or nonliving based on cellular evidence. This assesses understanding of cell composition, structure-function relationships, and the distinction between living and nonliving things across the unit.

Students may demonstrate understanding through a labeled diagram with teacher-provided word bank, oral explanation of cell structures and their functions, or a simplified data collection sheet with visual supports such as picture cards or color-coded organizers to organize information about living versus nonliving things.

Students with IEPs may benefit from graphic organizers that visually map cell structures to their functions, supporting both comprehension and the modeling tasks central to this unit. Provide scaffolded note-taking guides that chunk information about levels of biological organization into manageable sections, reducing the cognitive load of tracking multiple vocabulary-heavy concepts at once. For research and written explanation tasks, allow students to demonstrate understanding through oral responses, labeled diagrams, or dictation as alternatives to extended writing. Extended time and access to text-to-speech tools should be made available for reading-heavy source materials used during the research project.

Students with 504 plans should be given extended time for laboratory observations and written responses, particularly when precision in recording microscopic data or explaining cell function is required. Preferential seating near the front during demonstrations of microscopy or body system models ensures these students can fully access visual content. Printed copies of any diagrams, charts, or directions projected on the board should be provided so students can annotate and reference materials at their own pace throughout the unit.

Multilingual learners benefit from a dedicated visual word wall featuring key unit vocabulary—such as cell, organelle, tissue, organ, stimulus, and response—paired with labeled diagrams and, where possible, translations or cognates in students' home languages. Directions for laboratory investigations and modeling activities should be given in short, clear steps, with visual supports accompanying each stage of the task. Encourage students to use diagrams and labeled drawings as a primary mode of showing understanding, which allows them to demonstrate knowledge of cell structure and body systems without full dependence on academic English prose.

Students who need additional support should be connected to the unit's big ideas through concrete, hands-on entry points such as physical models or visual representations of cell structures before moving to more abstract descriptions of function and organization. Breaking the levels of biological organization into one focused layer at a time—starting with cells before progressing to tissues, organs, and systems—helps students build understanding incrementally without feeling overwhelmed by the full hierarchy at once. Providing partially completed graphic organizers and sentence frames for written explanations gives students a manageable starting point and reinforces key vocabulary in context as they work toward independence.

Advanced students can deepen their engagement with this unit by investigating how a specific cell type or body system is optimized for its function, drawing connections between cellular specialization and the broader physiological needs of an organism. Encourage them to evaluate the strengths and limitations of different cell models—including their own—by applying criteria such as accuracy, scale, and explanatory power, pushing their thinking beyond representation toward scientific critique. For the research project, these students can pursue focused questions that extend into emerging areas such as how the nervous system interfaces with other body systems or how cellular dysfunction relates to disease, drawing on sources at a more advanced level and generating substantive follow-up questions that reflect depth of inquiry.