pith

(noun)

the soft spongy substance in the center of the stems of many plants and trees

Related Terms

Examples of pith in the following topics:

  • Stem Anatomy

    • The ground tissue towards the interior of the vascular tissue in a stem or root is known as pith, while the layer of tissue between the vascular tissue and the epidermis is known as the cortex .
    • The central pith (greenish-blue, in the center) and peripheral cortex (narrow zone 3–5 cells thick, just inside the epidermis) are composed of parenchyma cells.
    • Vascular tissue composed of xylem (red) and phloem tissue (green, between the xylem and cortex) surrounds the pith.
    • The central pith and outer cortex of the (a) flax stem are made up of parenchyma cells.

  • The Evolution of Roots in Seedless Plants

    • In dicot roots, the xylem and phloem of the stele are arranged alternately in an X shape, whereas in monocot roots, the vascular tissue is arranged in a ring around the pith.