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The upcoming discussion will update you about the differences between Dicot Stems and Monocot Stems.
Difference # Dicot Stems:
1. Stomata have kidney-shaped guard cells.
2. The hypodermis is made up of collenchyma which may be green.
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3. The internal tissues are arranged in concentric layers.
4. The ground tissue is differentiated into cortex, endodermis, pericycle, pith, etc.
5. The stem is almost always solid.
6. The vascular bundles are arranged in ring around the pith.
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7. Medullary rays occur in between vascular bundles for radial conduction.
8. The vascular bundles are fewer in number and are of similar size.
9. The vascular bundles are wedge-shaped in outline.
10. No bundle sheath is present on the outside of a vascular bundle.
11. The vascular bundles are open due to the presence of cambium in between phloem and xylem.
12. Phloem parenchyma is present in the phloem along with other elements.
13. The stem shows secondary growth due to the formation of secondary vascular tissues and periderm.
14. Vessels are polygonal in outline.
15. Vessels are usually arranged in chains or rows.
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16. Metaxylem vessels are generally numerous.
17. A cavity is not found in the vascular tissues.
18. The older vascular tissues stop functioning after some time. They are replaced by younger vascular tissues.
19. The stem shows increase in diameter with-age.
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20. Old stem is covered by a corky bark.
Difference # Monocot Stems:
1. Stomata usually possess dumb bell-shaped guard cells.
2. The hypodermis is formed of non-green sclerenchyma fibres.
3. The concentric arrangement of tissues is absent.
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4. The ground tissue is a mass of similar cells.
5. The stem is generally hollow in the center (exception Maize).
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6. The vascular bundles are scattered throughout the ground tissue.
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7. Medullary rays are absent.
8. The vascular bundles are numerous and are of different sizes— smaller towards the outside and larger towards the centre.
9. They are oval or rounded in outline.
10. A sclerenchymatous bundle sheath is generally present on the outside of each vascular bundle.
11. The vascular bundles are closed.
12. Phloem parenchyma is absent.
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13. Secondary growth is usually absent.
14. Vessels are oval or rounded.
15. Vessels are arranged in a Y-shaped manner.
16. Metaxylem vessels are a few in number.
17. A cavity containing water is found in vascular bundle by the dissolution or separation of some protoxylem vessels and parenchyma cells lying nearby.
18. The first formed vascular tissues continue functioning throughout the life of the plant.
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19. There is little increase in diameter with age.
20. No additional structure is produced for protection of old stem. Persistent leaf bases occur in some.
