The micrograph shows a cross-section of a plant stem.
[VISUALIZATION: Micrograph of a dicot stem cross-section showing vascular bundles arranged in a ring, with labelled epidermis, cortex, phloem, xylem, and pith.]
(a) Identify the tissue labelled X. [1]
(b) Outline the function of the tissue labelled Y. [1]
(c) Draw a plan diagram to show the distribution of tissues in this stem section. [3]
(d) State the function of the cortex. [1]
(e) State one difference between the structure of a stem and a root in a dicot plant. [1]
Question
Identify the tissue labelled X. [1]
Hint
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Hint
Look for thick‑walled cells on the inner side of each vascular bundle.
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Question
Outline the function of the tissue labelled Y. [1]
Hint
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Hint
Recall that phloem moves products of photosynthesis throughout the plant.
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Transport of organic compounds (sugars) from source to sink
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Question
Draw a plan diagram to show the distribution of tissues in this stem section. [3]
Hint
Hint
Hint
Include a circular outline, ring of vascular bundles, and label epidermis, cortex, vascular bundles and pith.
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Plan diagram: Circular outline representing stem; ring of discrete vascular bundles each with phloem outer and xylem inner; labelled epidermis, cortex, bundles and central pith.
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Question
State the function of the cortex. [1]
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Hint
Think about storage and support roles of cortical parenchyma.
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Storage of food (e.g., starch) and support
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Question
State one difference between the structure of a stem and a root in a dicot plant. [1]
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Hint
Consider vascular bundle arrangement or presence of root hairs.
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Stem has vascular bundles in a ring and a central pith; root has a central vascular cylinder (stele) and root hairs.
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