Linear Diffusion and Cell Signaling

Subject
Biology
Chemistry
Education Level
High School
In this activity, students explore the concept of diffusion as a component of cell communication. Specifically, students will explore how the rate of diffusion varies with distance and concentration gradient. They will use a pipet with water and dye to observe a macro-model of diffusion. Additionally in the optional extension, students may explore how diffusion is affected by other factors such as medium type, temperature, molecular weight, shape of container (non-linear diffusion) or any other variable.
Purpose. This lab is designed to help students understand:
- Difficulties involved in measuring objects, especially irregular or small objects.
- How to define or describe diffusion.
- Qualitative descriptions of concentration and dilution.
- Methods of cell communication.
- Construct an investigative lab (optional)