AQA · GCSE · Biology
Course version: 8461 · Version from Sept 2018
Plant and algal cells also have a cell wall made of cellulose, which…
Full specification wording
Animal and plant cells: Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell.
Plant and algal cells have a cell wall outside the cell membrane.
Checked against the AQA 8461 specification (opens in a new tab) on .
- Point 4 of 8
- 2 key terms
Study notes
From the checked teaching notes for this specification point.
The idea
Plant and algal cells have a cell wall outside the cell membrane. It is made of cellulose, a carbohydrate polymer of glucose units. The wall is freely permeable, so it does not control what enters or leaves the cell; that is the role of the cell membrane. Its main function is strength and support. Cellulose forms strong fibres that resist stretching, so the wall helps the cell keep its shape and prevents it bursting when water enters by osmosis. This is why plant cells can become turgid and firm, supporting leaves and stems. For example, a root hair cell has a cellulose wall that helps it keep its long, narrow shape as it absorbs water. Animal cells have no cell wall, so they can change shape and may burst if too much water enters.
What earns the marks
- States that plant and algal cells have a cell wall outside the cell membrane.
- Identifies cellulose as the material of the cell wall.
- Explains that the wall strengthens and supports the cell and helps it keep its shape.
- Links the wall to preventing the cell bursting when water enters by osmosis.
- Contrasts plant and algal cells with animal cells, which lack a cell wall.
Common mistakes and how to put them right
Saying the cell wall controls what enters and leaves the cell.
Put it right by stating that the cell membrane is partially permeable and controls movement, while the wall is freely permeable.
Describing the wall as made of protein or chitin.
Put it right by naming cellulose as the carbohydrate polymer.
Placing the cell wall inside the cell membrane.
Put it right by stating that the wall lies outside the membrane.
Exam tips
- Use the word 'cellulose' explicitly whenever you describe the plant cell wall.
- When explaining turgidity, mention water entering by osmosis and the wall resisting the pressure.
- In comparison questions, state clearly that animal cells have no cell wall rather than leaving it implied.
Try the lesson
The start of the Animal and plant cells: Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell. lesson, made from checked teaching notes for this specification point.
Have a go first
What substance makes up the cell wall of plant and algal cells?
Listen
Plant and algal cells have a cell wall outside the cell membrane. It is made of cellulose, a carbohydrate polymer of glucose units. The wall is freely permeable, so it does not control what enters or leaves the cell; that is the role of the cell membrane. Its main function is strength and support. Cellulose forms strong fibres that resist stretching, so the wall helps the cell keep its shape and prevents it bursting when water enters by osmosis. This is why plant cells can become turgid and firm, supporting leaves and stems. For example, a root hair cell has a cellulose wall that helps it keep its long, narrow shape as it absorbs water. Animal cells have no cell wall, so they can change shape and may burst if too much water enters. A strong answer earns marks for these points. States that plant and algal cells have a cell wall outside the cell membrane. Identifies cellulose as the material of the cell wall. Explains that the wall strengthens and supports the cell and helps it keep its shape. Links the wall to preventing the cell bursting when water enters by osmosis. A common slip: Saying the cell wall controls what enters and leaves the cell. Instead, stating that the cell membrane is partially permeable and controls movement, while the wall is freely permeable. Exam tip: Use the word 'cellulose' explicitly whenever you describe the plant cell wall.
Key words
Say what each word means before you turn the card.
Cell wall
Try answering aloud or in your head before turning the card.
Cellulose
Try answering aloud or in your head before turning the card.
See every definition
- Cell wall
- A structure outside the cell membrane of plant and algal cells, made of cellulose, which strengthens the cell.
- Cellulose
- A carbohydrate polymer of glucose units that forms strong fibres resisting stretching, and is the material of the cell wall.
There is more to this lesson
The full lesson goes on to check your understanding and help you earn the marks. Create a free account to carry on, with your progress saved.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge
Test your understanding of Animal and plant cells: Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell.
Active recall beats re-reading. Take an instant quiz now to test what you’ve learned and lock it into long-term memory.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge