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# What makes a plant cell different?

Year 8 Biology · Cells

<!-- Speaker note: Students identify the cell wall, chloroplasts and large vacuole as plant-only structures and explain each, describe mitochondria and ribosomes in both cell types, and link a cell's organelles to its job (AC9S8U01, nodes 4 and 5). About 25 minutes (Engage and Explore 7 min · Explain 11 min · Evaluate 3 min · Typical adds 3 min, Wider about 3 min). -->

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## Today

**We are learning to** plant cells have three parts animal cells don't: a cell wall for support, chloroplasts for photosynthesis and a large vacuole that keeps the cell firm. Both kinds have mitochondria (for energy) and ribosomes (for making proteins), and how many of each a cell has depends on its job.

- I can name the parts only plant cells have and say what each is for.
- I can say which parts plant and animal cells share.
- I can explain why some cells have more of one part than others.

<!-- Speaker note: Before class: A concept tutorial for introducing or revising the idea; it pairs with onion and cheek cell slides. Set the width with `?width=minimum`, `typical` (default) or `wider`. One lesson for two nodes (plant-specific structures, other organelles), after What does every cell have? and before Why are cells different shapes? Not hinge nodes. The misconceptions: animal cells have walls; plants don't need mitochondria because they photosynthesise; every plant cell has chloroplasts. The prediction and the Typical step target them. Board notes: the diagrams are not to scale and show only some mitochondria and chloroplasts. Ribosomes are too small to draw at this scale, so they appear in the questions only. Teacher: In your own words: the labelled pair of cells is the evidence. -->

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## Why it matters

> A tree can stand 80 metres tall without a single bone. A lettuce leaf goes limp in the fridge, then crisp again in cold water. Both come down to parts that only plant cells have.

<!-- Speaker note: Every cell has a nucleus, membrane and cytoplasm. This lesson finds the parts that are different, and why. -->

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<span style="background:#dbeafe; color:#1a1a1a; border:1.5px solid #3b82f6; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">💬 Discussion</span>

## Engage: predict

**Which of these does a plant leaf cell have that a cheek cell does not?**

- A nucleus
- A cell wall, chloroplasts and a large vacuole
- A cell membrane
- Mitochondria

<!-- Speaker note: What happens: A cell wall, chloroplasts and a large vacuole. Both cells have mitochondria, a nucleus and a membrane: plants release energy from food just as animals do. Take two or three predictions before anyone runs it. -->

<!-- Speaker note: Teacher: tally the predictions. 'Mitochondria' means the student thinks plants don't respire. -->

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<span style="background:#fef3c7; color:#1a1a1a; border:1.5px solid #f59e0b; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✍️ Activity</span>

## Explore it

{{embed: https://studio.learningwaypoints.com/tutorials/_playground-board/index.html?id=deck%2Fscience%2Fbiology-8%2Fplant-cells%2Fstep-2&code=widget%3A+cell%0Ashow%3A+animal%2C+plant%0Afind%3A+wall%2C+chloroplasts%2C+vacuole%0A&fresh=1}}

[Open this step in the tutorial](https://studio.learningwaypoints.com/tutorials/science/biology-8/plant-cells/?full=step-2#step-2)

<!-- Speaker note:  -->

<!-- Speaker note: Teacher: ask what the plant needs that each plant-only part provides. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## What happened?

* A cell wall, chloroplasts and a large vacuole. Both cells have mitochondria, a nucleus and a membrane: plants release energy from food just as animals do.

<!-- Speaker note: Reveal after running. Ask who predicted it, and what made them think so. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Jobs

**Match each part to its job.**

| | |
|---|---|
| `Cell wall` | A. Holds cell sap and keeps the cell firm |
| `Chloroplast` | B. Photosynthesis: captures light to make glucose |
| `Large vacuole` | C. Make proteins |
| `Mitochondria` | D. Release energy from food (respiration) |
| `Ribosomes` | E. Rigid support, so the plant holds its shape without a skeleton |

* Answer: Cell wall → E. Rigid support, so the plant holds its shape without a skeleton; Chloroplast → B. Photosynthesis: captures light to make glucose; Large vacuole → A. Holds cell sap and keeps the cell firm; Mitochondria → D. Release energy from food (respiration); Ribosomes → C. Make proteins

<!-- Speaker note: The first three are only in plant cells (walls also in fungi and bacteria). Mitochondria and ribosomes are in both. -->

<!-- Speaker note: Teacher: the matching and the sort are the success criteria; the lettuce and muscle questions are the 'why'. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Plant only or both

**Plant cells only, or both plant and animal cells?**

Groups: Plant only · Both

Cell wall · Chloroplasts · Large permanent vacuole · Mitochondria · Ribosomes · Nucleus

* Answer: Cell wall → Plant only; Chloroplasts → Plant only; Large permanent vacuole → Plant only; Mitochondria → Both; Ribosomes → Both; Nucleus → Both

<!-- Speaker note:  -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## No chloroplasts

**Why don't animal cells need chloroplasts?**

- Animals get their food by eating, so they don't make it from light
- Animal cells are too small for chloroplasts
- Animals live where there is no light

* Answer: Animals get their food by eating, so they don't make it from light

<!-- Speaker note: Plants make their own food by photosynthesis; animals eat. Each cell's parts match how the organism lives. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## A limp lettuce

**A lettuce leaf goes limp when it loses water. Which part explains this?**

- The vacuoles shrink, so the cells push less against their walls
- The cell walls dissolve
- The chloroplasts stop working

* Answer: The vacuoles shrink, so the cells push less against their walls

<!-- Speaker note: A full vacuole presses the cell against its wall and keeps it firm. Lose water and the cell goes soft: the leaf wilts. Put it in water and it firms up again. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Many mitochondria

**A muscle cell has far more mitochondria than a skin cell. Why?**

- Mitochondria make muscles strong
- Muscle cells are bigger
- Contracting needs a lot of energy, and mitochondria release it

* Answer: Contracting needs a lot of energy, and mitochondria release it

<!-- Speaker note: Cells have the parts their job needs, in the numbers it needs: same DNA, different organelles. -->

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<span style="background:#fef3c7; color:#1a1a1a; border:1.5px solid #f59e0b; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✍️ Activity</span>

## Elaborate: a root hair cell

{{embed: https://studio.learningwaypoints.com/tutorials/_playground-board/index.html?id=deck%2Fscience%2Fbiology-8%2Fplant-cells%2Fstep-4&code=widget%3A+cell%0Ashow%3A+roothair%2C+plant%0A&fresh=1}}

[Open this step in the tutorial](https://studio.learningwaypoints.com/tutorials/science/biology-8/plant-cells/?full=step-4#step-4)

<!-- Speaker note: What this step is for: A plant cell without chloroplasts shows that parts depend on the cell's job, not just on being a plant. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## No chloroplasts

**Root hair cells have no chloroplasts. Why not?**

- They are not plant cells
- Chloroplasts would make them too heavy
- They are underground, with no light to photosynthesise; their job is taking in water

* Answer: They are underground, with no light to photosynthesise; their job is taking in water

<!-- Speaker note: A cell has the parts its job needs. Chloroplasts in the dark would be useless. -->

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<span style="background:#fef3c7; color:#1a1a1a; border:1.5px solid #f59e0b; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✍️ Activity</span>

## Elaborate: energy for movement

{{embed: https://studio.learningwaypoints.com/tutorials/_playground-board/index.html?id=deck%2Fscience%2Fbiology-8%2Fplant-cells%2Fstep-5&code=widget%3A+cell%0Ashow%3A+muscle%0A&fresh=1}}

[Open this step in the tutorial](https://studio.learningwaypoints.com/tutorials/science/biology-8/plant-cells/?full=step-5#step-5)

<!-- Speaker note: What this step is for: Linking organelle numbers to a cell's work extends 'specialisation' from shape to what is inside. -->

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Protein factories

**Cells in a gland that makes digestive enzymes (proteins) are packed with one organelle. Which?**

- Ribosomes, which make proteins
- Chloroplasts
- Vacuoles

* Answer: Ribosomes, which make proteins

<!-- Speaker note: Enzymes are proteins, and ribosomes make proteins. Like mitochondria in muscle, the number of an organelle follows the job. -->

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## Evaluate: look back

Write one sentence: "At first I thought… Now I think… because…"

**Revision summary**

- Only plant cells have a **cell wall** (support), **chloroplasts** (photosynthesis) and a **large vacuole** (keeps the cell firm, stores sap).
- Plant and animal cells both have a nucleus, membrane, cytoplasm, **mitochondria** (release energy from food) and **ribosomes** (make proteins).
- How many of each part a cell has depends on its job: muscle cells have many mitochondria; root hair cells have no chloroplasts.

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<span style="background:#dcfce7; color:#1a1a1a; border:1.5px solid #22c55e; padding:6px 18px; border-radius:8px; font-size:1em; font-weight:500;">✅ Check</span>

## Exit ticket

**Name two parts a leaf cell has that a cheek cell lacks, and say what each does.**

* Any two of: cell wall (support), chloroplasts (photosynthesis), large vacuole (keeps the cell firm, stores sap).

<!-- Speaker note: Students answer on paper or a mini whiteboard before the reveal. Anyone who cannot answer needs the main idea again next lesson. Where this leads: Next: Why are cells different shapes? (specialisation, AC9S8U02 node 1). In class: onion skin and Elodea leaf (chloroplasts visible) beside cheek cells; wilted and crisp lettuce in salt water and fresh water. -->