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Weekly Plan 4
Membrane transport
Student book links
Specification links
Link to GCSE specification
Suggested time allowed:
 1.1.10
 1.1.11
 1.1.12
 1.1.2 (h)-(j)
 Diffusion
 Osmosis
Six hours
Lesson time allocated:
Suggested teaching order
Weekly learning outcomes
Students should be able to:
 Explain what is meant by passive transport (diffusion and facilitated diffusion including the role of
membrane proteins), active transport, endocytosis and exocytosis.
 Explain what is meant by osmosis, in terms of water potential (no calculations of water potential will
be required).
 Recognise and explain the effects that solutions of different water potentials can have upon plant
and animal cells.
1. Demonstration and understanding of diffusion
2. What affects the rate of diffusion?
3. Need for facilitated diffusion and role of membrane in
controlling what enters the cell
4. Active transport
5. Bulk transport
6. Diffusion of water, water potential and osmosis
Key words
How science works
Diffusion. Facilitated diffusion. Protein. Concentration gradient. ATP. Kinetic energy.
Photosynthesis. Microvilli. Channel protein. Carrier protein. Glucose. Protein. Organelle. Cell
surface membrane. Respiration. Amino acid. Hormone. Lipid. Hydrophobic. Hydrophilic.
Diffusion gradient. Active transport. Endocytosis. Exocytosis. Chlorophyll. Complementary.
Endoplasmic reticulum. Vesicle. Hormone. Golgi apparatus. Lysosome. Phagocyte. Osmosis.
Water potential. Water potential gradient. Solvent. Solution. Solute. Partially permeable
membrane. Plasmolysis. Haemolysis. Turgid. Crenation. Plasmolysis.
 HSW 4 & 5 Investigative work
Learning styles (S = Starter activities, M = Main activities, P = Plenary activities)
ICT activities
 Animation: A wide variety of animations on biological processes
 Images: Cell membrane
 Use of animation in P1 and Excel/word processor in M1 and
M2.
 Use of Internet in Homework suggestions section and search
engines in Extension ideas section
Kinaesthetic
Activity S2&S3
Activity M1&M2
Activity P2
Interpersonal
Activity S1–S3
Activity M1&M2
Activity P1
Auditory
Activity S3
Activity M1&M2
Activity P1
Visual
Activity S1–S3
Activity M1–M3
Activity P1–P3
© Pearson Education Ltd 2008
This document may have been altered from the original
1
Weekly Plan 4
Suggested starter activities
Equipment
Teacher notes
1. Demonstrate diffusion using, for example, iodine in starch.
Ask students to role-play what is happening.
Iodine, starch suspension, beaker, pipette
Cluster students in one corner and ask them to diffuse. They
often walk away, instead of moving randomly, leaving an
empty space in the corner.
2. Provide the topic: Transport across a membrane. Pupils
add to the board words they think are relevant. Play in teams.
Each team sends a runner to the board to write a relevant
word. Develop the main ideas from the words they put up.
3. Each group writes a definition of diffusion and/or osmosis
and passes it to the next group to add to or amend.
The final group annotates the definitions to explain the
words. Select the best definition to present to the class.
Suggested main activities
Equipment
Teacher notes
1. Activity 2: Investigating different water potentials on plant
cells
Activity 3: Investigating water potential of swede
See Activity 2
See Activity 3
See Activity 2
See Activity 3
2. Activity 4: Effect of temperature on diffusion rate
Activity 5: Investigating the rate of diffusion through a
membrane
See Activity 4
See Activity 5
See Activity 4
See Activity 5
3. Activity 6: Investigating osmosis in an artificial cell
Activity 7: Serial dilutions
See Activity 6
See Activity 7
See Activity 6
See Activity 7
Suggested plenary activities
Equipment
Teacher notes
1. Use the animations as a class stimulus to assess students’
understanding. Ask pupils to explain what is happening in
each case.
Internet, projector, computer
Animation: Osmosis
Animation: Membrane transport
Please note that these animations are purposely in French
so that students can’t just read the descriptions, they have
to understand the animation then explain in their own words.
2. Students can sequence sets of statements or diagrams to
explain what happens during diffusion, osmosis, facilitated
diffusion etc.
Set of statements/diagrams as described
3. Students could explain what happens when Visking tubing
bags are put into strong sucrose solution, weak sucrose
solution and pure water.
Visking tubing bags, boiling tubes,
solutions as described
Construct three Visking tubing bags of weak sucrose
solution
© Pearson Education Ltd 2008
This document may have been altered from the original
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Weekly Plan 4
Homework suggestions
Cross-curriculum links
Extension ideas
 Investigate why Paramecium has a contractile vacuole.
 Hypothesise and plan an investigation to examine how halophytic plants that live in salt marshes can survive.
Potential misconceptions
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Never refer to water concentration, or the concentration gradient of water. This can lead to unnecessary confusion.
Students often forget the word net. This can indicate fundamental misconceptions about the nature of diffusion as dependent on random movement of particles.
Maximum water potential being zero often confuses students. Sometimes it’s useful to talk about water potential as more negative (lower) or less negative (higher).
Relate channel and carrier protein function back to protein structure at every opportunity to reinforce how their function is dependent on structure.
Notes
The web links referred to here are some that the author has found personally helpful but are not intended to be a comprehensive list, many other
good resources exist.
© Pearson Education Ltd 2008
This document may have been altered from the original
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