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Phloem Cell Differentiation
New phloem cells form when unspecialised plant cells differentiate and become specialised.
| Part shown | Visible features |
|---|---|
| Cell X | A small plant cell beside the phloem cell. It contains many oval organelles with folded inner membranes. A large clear internal compartment is labelled Y. |
| Phloem cell | An adjacent elongated plant cell with very little visible cell contents, no visible nucleus and an end wall containing many small openings. |
Describe one change in structure that occurs when an unspecialised cell differentiates to form a phloem cell.
Use Figure 3.
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Marking points
- 1 Describes one accepted structural change during differentiation into a phloem cell.
Full-mark answer
The differentiating cell loses its nucleus.
Why this answer loses marks
The phloem cell becomes long.
This only describes shape, which is ignored; identify a structure that is lost, formed or enlarged during differentiation.