Osmosis

Definition

Osmosis is the passive movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration. It is critical for maintaining cellular homeostasis.

5 Must Know Facts For Your Next Test

1. Osmosis occurs without the need for energy input, making it a form of passive transport.
2. In prokaryotic cells, osmosis helps regulate the internal environment by balancing water and solute levels.
3. The cell wall in prokaryotes provides structural support to prevent cell lysis due to excessive osmotic pressure.
4. Hypertonic environments cause prokaryotic cells to lose water and shrink, whereas hypotonic environments can lead to cell swelling.
5. Aquaporins are specialized membrane proteins that facilitate the rapid transport of water molecules during osmosis.

Review Questions

• What role does osmosis play in maintaining cellular homeostasis in prokaryotic cells?
• How do hypertonic and hypotonic environments affect prokaryotic cells differently?
• What function do aquaporins serve in the process of osmosis?

Related terms

Diffusion: The movement of particles from an area of high concentration to an area of low concentration.

Selective Permeability: A property of cellular membranes that only allows certain molecules to enter or exit the cell.

Aquaporins:

Membrane proteins that facilitate the rapid passage of water through cell membranes.