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

That suggested that C4 plants had at some point tacked ancestral regulatory elements for bundle sheath genes onto photosynthesis genes, so that DOFs would turn on both sets of genes at the same time.

From Science Daily • Nov. 20, 2024

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 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

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

The bundle sheath is not so plain here as in the fern.

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