LAUNCH · Edexcel GCSE Biology 1BI0 Foundation · Paper 1 · Topic 1 · Week 5
| Key word | What it means |
|---|---|
| osmosis | The net movement of WATER from a dilute to a concentrated solution through a partially permeable membrane. |
| partially permeable | Lets some substances cross more readily than others; this model permits water but not the represented sugar. |
| dilute | More water, less solute. |
| concentrated | Less water, more solute. |
| solute | The dissolved substance, e.g. sugar or salt. |
Session plan: 40-minute session: Arrival 3; overview 1; I Do 1 4; We Do 1 4; I Do 2 3; We Do 2 4; independent work 15; feedback and next step 3; exit 3. Title orientation is untimed. The optional two-minute evidence check sits inside independent time. Keep extra practice available; use the core question, a contrasting example and a recheck before extending.
Name: ____________________ Tier ringed by adult: ◆ Supported ▲ Standard ★ Stretch Date:
I can define osmosis and explain how it differs from diffusion.
Complete from the word bank: osmosis is the movement of ____ through a ____ membrane.
Write a definition of osmosis.
Write a definition of osmosis and state one way it differs from diffusion.
Water across a partially permeable membrane → ______________________________
Oxygen into the blood at the alveoli → ______________________________
Water from dilute to concentrated → ______________________________
A smell spreading across a room → ______________________________
Sugar crossing the membrane → ______________________________
Net movement of water down its gradient through a membrane → ______________________________
Osmosis is the net movement of water from a dilute solution to a concentrated solution through a partially permeable membrane. It is a special case of diffusion because only water moves, and it moves down its own concentration gradient.
You write the definition to the marking standard: 'Osmosis is the net movement of WATER from a DILUTE solution to a CONCENTRATED solution through a PARTIALLY PERMEABLE membrane.' Four phrases underlined. Read it back and check all four are there.
osmosis, partially permeable, dilute, concentrated, solute
You write the definition to the marking standard: 'Osmosis is the net movement of WATER from a DILUTE solution to a CONCENTRATED solution through a PARTIALLY PERMEABLE membrane.' Four phrases underlined. Read it back and check all four are there.
osmosis, partially permeable, dilute, concentrated, solute
You write the definition to the marking standard: 'Osmosis is the net movement of WATER from a DILUTE solution to a CONCENTRATED solution through a PARTIALLY PERMEABLE membrane.' Four phrases underlined. Read it back and check all four are there.
osmosis, partially permeable, dilute, concentrated, solute
Task: Label the osmosis diagram and complete the definition from the word bank.
Task: Write the osmosis definition unaided, then explain why the represented sugar does not cross this model membrane.
Task: Write the definition, explain why the represented sugar does not cross this model membrane, and describe one way osmosis differs from diffusion.
Why does the represented sugar not cross the membrane in this model?
Pearson Edexcel GCSE (9–1) Biology 1BI0 (Foundation, grades 1–5); GCSE Combined Science 1SC0 F where appropriate; AQA UAS science units
Records what was observed, and at which level of independence.
| Pupil | ____________________ |
| Lesson | Discover: Osmosis — LAUNCH Science · Week 5 |
| Date | ____________________ |
Observed in this lesson
☐ Defined osmosis including 'partially permeable membrane'.
☐ Stated water moves from dilute to concentrated.
☐ Explained osmosis as a special case of diffusion.
Assessor comment
Ring the tier the pupil actually worked at
| ◆ Supported | ▲ Standard | ★ Stretch |
Assessor name ______________ Role ____________ Signature ______________ Date ________
Space: This is a definition lesson — precision matters more than speed. The four key phrases stay on the board all lesson.
Voice: If 'water moves to the sugar' feels more natural to you, say so — then we reframe it by water together.
Audience: Your definition goes into the Topic 1 folder and is the springboard for next lesson's practical.
Influence: The class picks the everyday example (a wilting plant, a raisin in water) we open the practical with.
Closing the loop: this one ends on paper — your own hand, or your words scribed by an adult. Saying it aloud starts the loop; writing it is what closes it. Pass is always allowed.
What I said, and what it changed:
Keep with your portfolio.
| Pupil name: | Date: |
| WWW (What Went Well): | |
| EBI (Even Better If): | |
| Level worked at: Supported / Standard / Stretch | Evidence filed: Yes / Not yet |
| Pupil response — my next step: | |