- a layer of cells in plant leaves and stems that surrounds a vascular bundle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for bundle sheath
On account of this bundle-sheath the bundles are called fibro-vascular bundles.
In the vascular bundles of the ground tissue the bundle-sheath is rather prominent and the phloëm portion is well developed.
- A layer or region of compactly arranged cells surrounding a vascular bundle in a plant. The bundle sheaths regulate the movement of substances between the vascular tissue and the parenchyma and, in leaves, protect the vascular tissue from exposure to air.
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