Cell transport: diffusion, osmosis, and active pumps

What you’ll practice

From concentration gradients to membrane proteins, this quiz helps you apply core cell-transport ideas the way they appear in class tests and labs.

You’ll work through diffusion vs. osmosis, tonicity outcomes for cells, and when transport needs ATP—without relying on rote definitions.

Quiz format and difficulty

Each question has 4 options and there’s no timer, so you can slow down and reason through graphs, setups, and “what happens next?” prompts.

Pick your question count before you start, and choose an easier or harder setting; the mixed difficulty option balances straightforward recall with multi-step application.

Common pitfalls to avoid

Many mistakes come from mixing up solute vs. water movement, assuming “high to low” always applies the same way, or forgetting that membrane permeability changes the outcome.

Watch for wording like hypertonic/hypotonic/isotonic, and remember that active transport can move against a gradient but depends on energy and specific pumps.

Quick tips for better scores

• Identify what’s moving (water or solute) before choosing a direction
• Compare inside vs. outside concentrations to determine tonicity
• Separate simple diffusion from facilitated diffusion (protein required)
• Check whether ATP is implied (pumps, cotransport, gradients maintained)
• Don’t assume size alone decides permeability; polarity and channels matter
• Use equilibrium language carefully: dynamic movement can continue even at balance