The cell’s scaffolding

The idea

In eukaryotic cells a network of fine fibres, the cytoskeleton, provides structural support, maintains cell shape, and enables cell movement and internal transport.

A tent without poles

A tent keeps its shape because of its poles and ropes. Without them it sags in a heap.

What might keep a cell’s shape in the same way?

• A network of fine fibres inside
• Nothing; cells have no shape
• Only the nucleus

Remove the fibres

Take the cytoskeleton away. Then put it back.

The cytoskeleton

In eukaryotic cells, a network of fine fibres, the cytoskeleton, provides structural support, maintains cell shape, and enables cell movement and internal transport.

It is visible only under an electron microscope as a separate entity.

• Job | How the fibres help
• Support | a framework inside the cell
• Shape | keeps the cell from sagging
• Movement | helps the cell move
• Transport | carries things inside the cell

Notes

The cytoskeleton is a network of fine fibres in eukaryotic cells. It gives support, keeps shape, and enables movement and internal transport.

Check yourself

The cytoskeleton is…

Which is not a job of the cytoskeleton?

To see the cytoskeleton as a separate structure, we need…

If a cell lost its cytoskeleton, what would be most affected?

• a network of fine fibres in eukaryotic cells — correct. Yes.
• the cell wall. The wall is outside the membrane.
• the nucleus. The nucleus is a separate organelle.
• Making ATP from glucose — correct. That is done in mitochondria.
• Giving structural support. The cytoskeleton does this.
• Keeping the cell’s shape. The cytoskeleton does this.
• Helping internal transport. The cytoskeleton does this.
• an electron microscope — correct. Yes.
• bare eyes. It is far too fine.
• a hand lens. It is far too fine.
• Its shape, and the movement of things inside it — correct. Yes.
• Nothing at all. The fibres do important jobs.
• Only its colour. The fibres are not about colour.