bundle sheath

American  

noun

Botany.

1. a layer of cells in plant leaves and stems that surrounds a vascular bundle.

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bundle sheath Scientific  

1. 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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Example Sentences

C4 plants recruit bundle sheath cells, which normally serve as leaf vein support, to photosynthesize alongside mesophyll cells.

From Science Daily • Nov. 20, 2024

In C4 plants, however, the spatial separation of the C4 photosynthesis pathway helps prevent O3 from infiltrating the bundle sheath cells where sugars are made.

From Science Daily • Nov. 13, 2023

Instead of using rubisco, bundle sheath cells in this ring use the enzyme phosphoenolpyruvate carboxylase, which doesn't bind oxygen, to capture CO2 in a four-carbon compound.

From Nature • Apr. 25, 2017

In C4 leaves, mesophyll cells radiate out around bundle sheath cells like spokes on a wheel, whereas in C3 leaves they are stacked on top of one another in a flat arrangement.

From Nature • Apr. 25, 2017

There is a bundle sheath of much-flattened cells separating the fibro-vascular bundle from the ground tissue.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton