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(cell and molecular biology)
A thin barrier which is formed across the spindle equator in late cytokinesis in plant cells and within which the cell wall is laid down.



in higher plants, a formation that arises between the daughter nuclei during cell division and that consists of microtubules, ducts of the endoplasmic network, and tiny pectin granules. In the equatorial plane of the phragmoplast there occurs an aggregation of bubbles, probably derivatives of the Golgi complex, which develop into a cellular septum, that is, a membrane that becomes the cell wall. Cellulose is deposited on both sides of the wall. Gradually, as the cell wall is formed, the phragmoplast moves toward the periphery of the mother cell and continues to function until there is closure of the newly formed cell wall with the membrane of the mother cell.

References in periodicals archive ?
Similar BMAs contribute to the development of complex phragmoplast systems (Fig.
Even though meiotic cytokinesis is delayed until after second division when it occurs simultaneously, a well-developed phragmoplast is typically organized in the equatorial region during anaphase/telophase I.
The mechanism of intracellular motility involved in OB development is not at all understood, especially since the organelles first appear to form a collar surrounding the interzone and then proceed to invade the region at right angles to the BMAs making up the phragmoplast.
Phragmoplast formation after second meiosis is complex and is mediated by a quadripolar structure of merged phragmoplasts similar in appearance to the initial QMS.
The primary phragmoplasts expand and secondary phragmoplasts form between non-sister nuclei resulting a phragmoplast complex (Fig.
29a-c) and give rise to a phragmoplast in which forms a free-floating disc.
Interaction of opposing sets of microtubules in the interzone gradually gives rise to a well-defined phragmoplast (Fig.
This results in a phragmoplast complex that directs cell plate deposition to simultaneously cleave the tetrad of spores.
Microtubules emanating from proximal surfaces of the nuclei and flanking plastids form a phragmoplast array (Fig.
gamma]-Tubulin organizes phragmoplast microtubules between sister nuclei in telophase II (Fig.
Primary phragmoplasts are initiated in the interzones of spindles and additional microtubules emanating from non-sister nuclei/plastids give rise to secondary phragmoplasts that interconnect the nuclei and define the division planes (Fig.