neoblast

biology

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July 1, 2026

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Neoblasts are large, undifferentiated cells found in annelid worms that play a crucial role in regeneration. These cells are particularly significant in flatworms, such as planarians, which are renowned for their remarkable regenerative capabilities.123

In flatworms, neoblasts are believed to be the source of cells that form new body parts, like heads and tails, when the organism is cut. These undifferentiated cells are rich in ribonucleic acid (RNA), which is essential for cell division, and they appear in large numbers during the regeneration process. While there is some debate about the exact origin of these regenerative cells, the presence and activity of neoblasts are strongly linked to the ability of these organisms to regrow lost parts.23

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biological development
Open and closed systems of development
…in which certain cells called neoblasts seem able to participate in any type of development; these cells are usually scattered throughout the body, and the major developmental processes that bring into being the general form of the organism cannot be attributed to them, as the development of the plant can…
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…in which certain cells called neoblasts seem able to participate in any type of development; these cells are usually scattered throughout the body, and the major developmental processes that bring into being the general form of the organism cannot be attributed to them, as the development of the plant can…
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flatworm
Turbellaria
…special type of cell, a neoblast, is involved in planarian regeneration. Neoblasts, rich in ribonucleic acid (RNA), which plays an essential role in cell division, appear in great numbers during regeneration. Similar cells, apparently inactive, occur in the tissues of whole organisms (see also regeneration: Biological regeneration).
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…special type of cell, a neoblast, is involved in planarian regeneration. Neoblasts, rich in ribonucleic acid (RNA), which plays an essential role in cell division, appear in great numbers during regeneration. Similar cells, apparently inactive, occur in the tissues of whole organisms (see also regeneration: Biological regeneration).
Read More