gemmule

1. (biology)Examples: "A very similar mode of growth and propagation is found among the compound Polypes, whose gemmules, like those of the Medusæ, are at first free, and moved by cilia; afterwards attached, and budding forth with a plant-like body."; "Accidental hematozoa may be found, […] in the vessels of man and other animals; these are foreign to the blood, and do not circulate with it. The hydatid, acephalocystis endogena, detaches its gemmules from its inner surface; one thus inclosing the other in a series, like pill-boxes. It is found in the liver, kidney, womb, etc."; "They [spores and tetraspores] may rather be considered, the one a true spore, supposed to be fertilized by means of an antheridium; the other, a mere gemmule, or bud of the simplest possible structure, which is cast off by the parent plant, and carries with it sufficient vitality to become the nucleus of a fresh individual."Synonyms: gemmaarchaic

2. (biology)Examples: "Sponges are propagated by gemmules, which originate in the organic mucus, and are carried out of the body by the effluent currents just described. In some sponges these gemmules are ciliated and locomotive when mature; but it seems probable that the majority of the species produce only unciliated gelatinous grains, which are nevertheless endowed with a very active motility, like the ultimate particles of even inorganic matter."; "The increase in size of the gemmule takes place by means of cell growth and division, and by the fusion of neighboring small gemmules."; "The green fresh-water sponge dies away in autumn, all but little pinhead clusters of cells called gemmules, which eventually float away from the dead skeleton and start new sponges in the spring."archaicspecifically

3. (biology)Examples: "[…] I assume that cells, before their conversion into completely passive or "formed material," throw off minute granules or atoms, which circulate freely throughout the system, and when supplied with proper nutriment multiply by self-division, subsequently becoming developed into cells like those from which they were derived. These granules for the sake of distinctness may be called cell-gemmules, or, as the cellular theory is not fully established, simply gemmules. […] Their development is supposed to depend on their union with other partially developed cells or gemmules which precede them in the regular course of growth. […] Lastly, I assume that the gemmules in their dormant state have a mutual affinity for each other, leading to their aggregation either into buds or into the sexual elements."; "Curse you, you wandering gemmule, / And nail you fast in Hell! / You gave me gout and bandy legs, / You beast, you wanted a cell! / Gout, and gravel, and evil days— / (Theology speaks, shaking her head) / But there is One who knows your ways!"; "This theory [of pangenesis] appears to be as follows: That each living organism is ultimately made up of an almost infinite number of minute particles termed "gemmules," each of which has power to reproduce its kind. […] That such a complete collection of gemmules is aggregated in each ovum and spermatozoon in most animals, and in each part capable of reproducing by gemmation (budding) in the lowest animals and in plants. Therefore in many of such lower organisms such a congeries of ancestral gemmules must exist in every part of the body, since in them every part is capable of reproducing by gemmation."historical

4. (botany) Synonym of plumule (“the first bud, or growing point, of a plant embryo, situated above the cotyledons”).Examples: "To what do this cavity which contains the gemmule, this thin layer which covers it, correspond? We have stated that the cotyledon is nothing else than the first leaf of the little vegetable, and the gemmule the union of the leaves which will follow it."; "The embryo is composed of cells and spiral vessels; a small stem, or stalklet; a rudimentary descending portion, which becomes the root or radicle; and a rudimentary ascending axis, surrounded by a bud, or gemmule. Between the radicle and the gemmule, the first leaves developed are termed cotyledons: a plant having leaves like seed-lobes."; "The incipient apical meristem (gemmule) is located between the two cotyledons of the mature embryo and consists of a pocket of approximately 200 meristematic cells[…]."Synonyms: plumule

5. (neurology) Synonym of dendritic spine (“a small membranous protrusion from the dendrite of a neuron that typically receives input from a single axon at the synapse”).Examples: "Concussion from shell explosion often sufficient to produce miliary hemorrhages in brain substance. Mott has found such lesions in brains of shell shock. Lesser lesions on fine nerve fibrils and gemmules, or nerve cells may reasonably be postulated."; "The mitral cells also extend several secondary dendrites (SD) laterally outward into the external plexiform layer (EPL), where they are in intimate association with the dendritic spines (or gemmules) belonging to the dendrites of the granule cell population, whose cell bodies (g) lie deeper in the granular layer (GRL) of the bulb."; "Two GAD-positive gemmules (D₁, D₂) from dendrites of periglomerular neurons form synapses with a mitral/tufted dendritic shaft (D₃). One gemmule (D₁) appears to form a reciprocal synapse, and the other gemmule (D₂) appears to be presynaptic only (original magnification × 54,000)."Synonyms: dendritic spine