pith

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stem cross section

apical meristems

Illustration of a tree trunk cross-section with labeled features including outer and inner bark, sapwood, heartwood, pith, and growth rings, plus radial, tangential, and transverse surfaces.

primary and secondary growth

pith

plant anatomy

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July 1, 2026

Quick Summary

stem cross section — stem cross section Light micrograph of a cross section of a Tilia stem. At centre is the pith, surrounded by a layer of wood (xylem). A thin cambium separates this from the phloem. An outer layer of collenchyma cells is enclosed by the outer bark.

The pith is a central strand of spongy tissue found in the stems of most vascular plants. It primarily functions in storage. In some plants, particularly young dicotyledons and gymnosperms, the vascular bundles are arranged in a circle around this central pith. The pith is composed of parenchyma cells, which are living, unspecialized cells adaptable to various functions like photosynthesis and food storage. In monocots, vascular bundles are scattered throughout the stem, and a distinct pith or cortex may not be present. The term "pith" can also refer to the essential part or core of something, metaphorically.12345

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angiosperm
Stems
…and that within is the pith. Ground tissue called the interfascicular parenchyma lies between the procambial strands and remains continuous with the cortex and pith. As the vascular tissue grows, xylem and phloem develop, the vascular bundles mature, the single-layered epidermis differentiates as epidermal cells, trichomes, and a few stomata,…
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…and that within is the pith. Ground tissue called the interfascicular parenchyma lies between the procambial strands and remains continuous with the cortex and pith. As the vascular tissue grows, xylem and phloem develop, the vascular bundles mature, the single-layered epidermis differentiates as epidermal cells, trichomes, and a few stomata,…
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plant
Stems
…central portion make up the pith. The outermost cells of the stem compose the epidermis. No bark is formed on the herbaceous stem. In contrast, woody dicot stems develop an outer layer of dead thick-walled cells called cork cells, which together with the underlying phloem compose the bark of the…
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…central portion make up the pith. The outermost cells of the stem compose the epidermis. No bark is formed on the herbaceous stem. In contrast, woody dicot stems develop an outer layer of dead thick-walled cells called cork cells, which together with the underlying phloem compose the bark of the…
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parenchyma
…the cortex (outer layers) and pith (innermost layers) of stems and roots; it also forms the soft tissues of fruits. Cells of this type are also contained in xylem and phloem as transfer cells and as the bundle sheaths that surround the vascular strands. Parenchyma tissue may be compact or…
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…the cortex (outer layers) and pith (innermost layers) of stems and roots; it also forms the soft tissues of fruits. Cells of this type are also contained in xylem and phloem as transfer cells and as the bundle sheaths that surround the vascular strands. Parenchyma tissue may be compact or…
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lower vascular plant
Other cells
The pith is made up of parenchyma cells as a rule, but, in some fern genera, scattered tracheid-like cells are found as well. The cells of the stems differ from those of many seed plants in lacking collenchyma (modified parenchyma cells with expanded primary walls) and…
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The pith is made up of parenchyma cells as a rule, but, in some fern genera, scattered tracheid-like cells are found as well. The cells of the stems differ from those of many seed plants in lacking collenchyma (modified parenchyma cells with expanded primary walls) and…
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starch
… of the potato; the stem pith of sago; and the seeds of corn, wheat, and rice. When required, starch is broken down, in the presence of certain enzymes and water, into its constituent monomer glucose units, which diffuse from the cell to nourish the plant tissues. In humans and other…
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… of the potato; the stem pith of sago; and the seeds of corn, wheat, and rice. When required, starch is broken down, in the presence of certain enzymes and water, into its constituent monomer glucose units, which diffuse from the cell to nourish the plant tissues. In humans and other…
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stem
Growth and anatomy
…spongy ground tissue called the pith. Surrounding the vascular bundles is a layer that varies in thickness in different species and is called the cortex. Surrounding this and comprising the exterior surface of the stem is a layer called the epidermis. In plants with woody stems, a variety of secondary…
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…spongy ground tissue called the pith. Surrounding the vascular bundles is a layer that varies in thickness in different species and is called the cortex. Surrounding this and comprising the exterior surface of the stem is a layer called the epidermis. In plants with woody stems, a variety of secondary…
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tree
General features of the tree body
… and the inner region the pith, although among many of the monocotyledons (an advanced class of angiosperms, including the palms and lilies) the ground tissue is amorphous and no regions can be discerned. The roots of woody dicots and conifers develop only a cortex (the pith is absent), the innermost…
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… and the inner region the pith, although among many of the monocotyledons (an advanced class of angiosperms, including the palms and lilies) the ground tissue is amorphous and no regions can be discerned. The roots of woody dicots and conifers develop only a cortex (the pith is absent), the innermost…
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