Diffusion: The net movement of particles from an area of higher concentration to an area of lower concentration
Example: Oxygen or glucose molecules diffusing into a cell
Osmosis
Osmosis: A special case of diffusion
Specifically, the diffusion of water molecules
Definition: Net movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration
Understanding Water Concentration
Water Concentration:
Refers to the amount of water compared to solutes (like sugars or salts) dissolved in it
Solutes: Molecules dissolved in water
Example with Beakers:
Two beakers with equal amounts of water
Left beaker has 1 solute particle; Right beaker has 3 solute particles
Right beaker:
Higher concentration of solutes
Lower concentration of water
Left beaker:
Lower concentration of solutes
Higher concentration of water
Key Point:
Concentration is determined by the proportion of water to solutes, not the volume of water
Application to Cells
Consider the cell structure:
Inside the cell: Many water and solute particles
Outside the cell: Almost pure water with few solute particles
Concentration Differences:
Outside the cell has higher water concentration (fewer solutes)
Inside the cell has lower water concentration (more solutes)
Osmosis in Cells:
Water particles move from outside (higher water concentration) to inside the cell (lower water concentration)
Additional Resources
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Conclusion
Understanding osmosis and water concentration is crucial for comprehending cellular processes
Further learning and practice are encouraged through the provided resources