Learn: Diffusion and Osmosis

Welcome!Today we'll explore diffusion and osmosis, two important processes in biology. These help substances move in and out of cells. Let's break it down step by step!

What is Diffusion?Diffusion is the movement of particles from an area of high concentration to an area of low concentration. It happens down a concentration gradient and doesn't require energy. It's how oxygen and carbon dioxide move into and out of cells.

What is Osmosis?Osmosis is the movement of water molecules through a selectively permeable membrane, from an area of higher water potential to an area of lower water potential. Like diffusion, it doesn't require energy.

Key Difference: Diffusion vs OsmosisDiffusion moves particles like gases or dissolved substances, while osmosis specifically moves water. Both occur passively without needing energy from the cell.

Why Are These Processes Important?Diffusion and osmosis are essential for cell survival. Diffusion allows oxygen and nutrients to enter cells and waste products like carbon dioxide to leave. Osmosis helps maintain the water balance within cells, preventing them from shrinking or bursting.

Visking Tubing: A Model for MembranesVisking tubing is used as a model to demonstrate diffusion and osmosis. Its small pores allow water and other small molecules to pass, but block larger molecules. Scientists use it to understand how cell membranes work.

Review Time!Great work! You've learned about diffusion, osmosis, and their importance in biology. Now let's test your understanding further with a few questions.