Learn: Diffusion and Osmosis

Welcome!Today we'll dive into diffusion and osmosis, two key processes for how substances move in and out of cells. Let's explore these 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 naturally and doesn’t require energy, which makes it a passive process.For example, oxygen diffuses into cells for respiration, while carbon dioxide diffuses out.

What is Osmosis?Osmosis is the movement of water across a selectively permeable membrane from an area of high water potential to low water potential. This process is essential for maintaining cell structure and function.For example, plant roots use osmosis to take up water from the soil.

Comparing Diffusion and OsmosisBoth diffusion and osmosis involve movement from high to low concentration, but osmosis specifically refers to water and requires a selectively permeable membrane.Diffusion can involve gases like oxygen or carbon dioxide, while osmosis is about water balance in cells.

Visking Tubing as a ModelVisking tubing is used to model how membranes work. It has small pores that allow water and smaller molecules to pass through, but blocks larger molecules like starch.This helps us understand selective permeability in membranes.

Review Time!Great work! You've explored diffusion, osmosis, and how membranes function. Let's test your understanding with a few more questions.