What two conditions must be present for osmosis to occur?

• A. A semipermeable membrane and a concentration gradient
• B. A permeable membrane and no concentration gradient
• C. Equal concentrations on both sides of the membrane
• D. A semipermeable membrane and equal solute concentrations

Answer: (A)

Verified step by step guidance

1. Understand the concept of osmosis: Osmosis is the movement of solvent molecules through a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.
2. Identify the role of a semipermeable membrane: A semipermeable membrane allows only certain molecules or ions to pass through it, typically allowing the solvent (like water) to pass while blocking solute particles.
3. Recognize the importance of a concentration gradient: A concentration gradient is necessary for osmosis to occur, as it provides the driving force for the movement of solvent molecules from an area of lower solute concentration to an area of higher solute concentration.
4. Evaluate the given options: Analyze each option to determine which conditions align with the requirements for osmosis. Look for the presence of a semipermeable membrane and a concentration gradient.
5. Conclude with the correct conditions: Based on the understanding of osmosis, identify that the correct conditions are a semipermeable membrane and a concentration gradient, as these are essential for the process to occur.