K325 / 2027

Chapter 2 / 6 short lessons

Movement of substances

Explain how substances enter and leave cells, and predict what happens when their surroundings change.

G3 Pure Biology / K325 / 2027 syllabus

What do you think?

A potato strip loses mass in sugar solution. What most likely moved?

Lessons

0 of 6 marked as read
01

Diffusion

Predict the net movement of particles from their concentration gradient.

About 4 min
About 4 min
02

Osmosis

Predict the net movement of water using water potential and membrane permeability.

About 4 min
About 4 min
03

Osmosis in plant and animal cells

Link water movement to changes in plant and animal cells.

About 5 min
About 5 min
04

Active transport

Explain movement against a concentration gradient using energy from respiration.

About 4 min
About 4 min
05

Diffusion, osmosis or active transport?

Choose the process using the substance, membrane and direction of movement.

About 3 min
About 3 min
06

Investigating osmosis

Calculate percentage mass change, interpret the evidence and plan a fair comparison.

About 6 min
About 6 min
What you will be able to do
  • Use concentration and water potential to predict net movement.
  • Explain the effects of osmosis on plant and animal cells.
  • Distinguish diffusion, osmosis and active transport.
  • Use experimental evidence to explain a change in mass.

Ready to try it without your notes?

Start with a quick check or explain a biological result in your own words.

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