https://learn.concord.org/resources/120/diffusion-osmosis-and-active-transport
Movement of ions in and out of cells is crucial to maintaining homeostasis within the body and ensuring that biological functions run properly. The natural movement of molecules due to collisions is called diffusion. Several factors affect diffusion rate: concentration, surface area, and molecular pumps. This activity demonstrates diffusion, osmosis, and active transport through 12 interactive models. Start by following the path of a molecule of dye in water, create concentration gradients on either side of a cell membrane and watch the movement of substances in and out of a cell, and monitor the movement of oxygen into red blood cells with and without hemoglobin.
PLEASE NOTE: This resource can be assigned, but student responses will not be saved.
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Performance Expectations
From Molecules to Organisms: Structures and Processes. Students who demonstrate understanding can: Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
Disciplinary Core Ideas
HS-LS1.A Structure and Function
Multicellular organisms have a hierarchical structural organization, in which any one system is made up of numerous parts and is itself a component of the next level.
HS-LS1.A Structure and Function
Feedback mechanisms maintain a living system's internal conditions within certain limits and mediate behaviors, allowing it to remain alive and functional even as external conditions change within some range. Feedback mechanisms can encourage (through positive feedback) or discourage (negative feedback) what is going on inside the living system.
Science and Engineering Practices
Developing and Using Models
Modeling in 9–12 builds on K–8 and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed worlds. Use a model based on evidence to illustrate the relationships between systems or between components of a system.
Engaging in Argument from Evidence
Engaging in argument from evidence in 9–12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about natural and designed worlds. Arguments may also come from current scientific or historical episodes in science. Make and defend a claim based on evidence about the natural world that reflects scientific knowledge, and student-generated evidence.
Analyzing and Interpreting Data
Analyzing data in 9–12 builds on K–8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. Analyze data using computational models in order to make valid and reliable scientific claims.
Crosscutting Concepts
Structure and Function
Complex and microscopic structures and systems can be visualized, modeled, and used to describe how their function depends on the shapes, composition, and relationships among its parts, therefore complex natural structures/systems can be analyzed to determine how they function.
Cause and Effect
Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.
Systems and System Models
Models (e.g., physical, mathematical, computer models) can be used to simulate systems and interactions—including energy, matter, and information flows—within and between systems at different scales.