number of undifferentiated gametes and has been termed a coenogamete.
A, Cell (individual) of the unicellular Green Alga Pleurococcus, as an example of an undifferentiated autonomous assimilating cell.
By budding is understood the formation of a new individual from a fresh growth of undifferentiated material.
From the primitive uniform Systems. mass of undifferentiated assimilating cells, which we may conceive of as the starting-point of differentiation, though such an undifferentiated body is only actually realized in the thallus of the lower Algae, there is, (1) on the one hand, a specialization of a surface layer regulating the immediate relations of the plant with its surroundings.
The remaining tissue of the plant-body, a tissue that we must regard phylogenetically as the remnant of the undifferentiated tissu~ of the primitive thallus, but which often undergoes further different,iation of its own, the better to fulfil its characteristically vital functions for the whole plant, is known, from its peripheral position in relation to the primitively central conducting tissue, as (3) the cortex.
Sometimes development stops altogether, and a layer of undifferentiated parenchyma (the mesodesm) is left between them; or it may continue indefinitely, the central cells keeping pace by their tangential division with the differentiation of tissue on each side.
It does not at first appear to be the same with the bulkier plants, such as the ordinary green herbs, shrubs or trees, but a study of their earlier development indicates that they do not at the outset differ in any way from the simple undifferentiated forms. Each commences its existence as a simple naked protoplast, in the embroyo-sac or the archegonium, as the case may be.
The Lymexylonidae, a small family of this group, characterized by its slender, undifferentiated feelers and feet, is believed by Lameere to comprise the most primitive of all living beetles, and Sharp lays stress on the undeveloped structure of the tribe generally.
- Under Roman rule Bosnia had no separate name or history, and until the great Slavonic immigration of 636 it remained an undifferentiated part of Illyria stations are Bjelina, Zvornik, Visegrad, Gorazda, Foea, Bilek, Avtovac and Trebinje, along the eastern frontier; Mostar and Stolac in the south; Livno in the west; and Bihac in the north.
It thus appears that white lead and sugar of lead were undifferentiated.
To Aristotle matter is the undifferentiated primal element: it is rather that from which things develop (U7roKE4tEvov, Siuvaµus) than a thing in itself (ivep-yeta).
The descendants of such cells will become more and more undifferentiated, thereby developing an increased vegetative activity.
Actual government in the feudal age was primitive and undifferentiated.
According to some writers (Leuckart) they are derived from undifferentiated blastomeres, other authorities (Thomas, Biehringer, Heckert) trace them to the parietal cells of the larva.
In the Eumenidae or solitary wasps the female sex is undifferentiated, and the foot claws are toothed.
Most of the genera are " solitary " in habit, the female sex being undifferentiated; but among the humble-bees and hive-bees we find, as in social wasps and ants, the occurrence of workers, and the consequent elaboration of a wonderful insect-society.
The identity, the absolute, which underlay all difference, all the relative, is to be characterized simply as neutrum, as absolute undifferentiated self-equivalence.
Either this part of the continent was largely land at this time, or the Silurian formations here have been worn away or remain undifferentiated.
BATHYBIUS (13aOus, deep, and (31os, life), a slimy substance at one time supposed to exist in great masses in the depths of the ocean and to consist of undifferentiated protoplasm.
If, on the other hand, the endosperm is the product of an act of fertilization as definite as that giving rise to the embryo itself, we have to recognize that twin-plants are produced within the embryo-sac - one, the embryo, which becomes the angiospermous plant, the other, the endosperm, a short-lived, undifferentiated nurse to assist in the nutrition of the former, even as the subsidiary embryos in a pluri-embryonic Gymnosperm may facilitate the nutrition of the dominant one.
The correlation between undifferentiated sets of serial homologues, produced by a single individual, is the measure of what Pearson has called homotyposis.
We may therefore conclude that for large classes of characters, both animal and vegetable, the variability of an individual, as measured by the standard deviation of its undifferentiated but repeated organs, is a constant fraction of the variability of its race, as measured by the standard deviation of the corresponding series of organs produced by all the individuals of its race.
They show the development of classes or parties in the old undifferentiated mass.
This has been since designated as polyzoism or panthelism or panvitalism, 2 and represents the obscure undifferentiated groundwork out of which Tylor's Animism arises.
An important consequence of thus giving the study of primitive religion the wide scope of a comparative hierology is that magic is no longer divorced from religion, since the sacred will now be found to be coextensive with the magicoreligious, that largely undifferentiated plasm out of which religion and magic slowly take separate shape as society comes more and more to contrast legitimate with illicit modes of dealing with the sacred.
s Out of the vast mass of undifferentiated powers certain functional deities appear; and the Kami of Japan to-day who preside over the gilds and crafts of industry and agriculture, over the trees and grasses of the field, the operations of the household, and even the kitchenrange, the saucepan, the rice-pot, the well, the garden, the scarecrow and the privy, have their counterparts in the lists of ancient Rome, the indigitamenta over whose contents Tertullian and Augustine made merry.
J.) History Throughout the centuries which witnessed the destruction of Carthaginian power by Rome, the establishment and decline of Latin civilization, the invasion by Alani, Suevi and other barbarian races, the resettlement under Visigothic rule and the overthrow of the Visigoths by Arab and Berber tribes from Africa, Portugal remained an undifferentiated part of Hispania, without sign of national consciousness.
The simpler forms of Edrioasteroidea, with their more sac-like body and undifferentiated plates, may well have been derived from early Cystidea of yet simpler structure, and there seems no reason to follow Jaekel in regarding the class as itself the more primitive.
The black represents the cuticular product of the epidermal cells of the ocular area, taking the form either of))...,r,, f lens, cl, of crystalline body, cry, or of rhabdom, rhab; hy, hypodermis or epidermal cells; corn', laterallyplaced cells in the simpler stage, A, which like the nerve-end cells, vit' and ret', are corneagens or lens-producing; corn, specialized corneagen or lens-producing cells; vie, potential vitrella cells with cry', potential crystalline body now indistinguishable from retinula cells and rhabdomeres; vit, vitrella cell with cry, its contained cuticular product, the crystalline cone or body; ret', rhab', retinula cells and rhabdom of scorpion undifferentiated from adjacent cells, vit'; ret, retinula cell; rhab, rhabdom; nf, optic nerve-fibres.
Recognized, in fact, already as separate provinces were Austrasia, or the eastern kingdom, Neustria, or north-west Gaul and Burgundy; Aquitaine alone was as yet undifferentiated.
A malignant tumour composed of undifferentiated masses of cells.
1 If the earliest conception is that of an obscure undifferentiated animation (panvitalism), the analysis of the human person into body and spirit with the corresponding doctrine of " objectsouls " (e.g.
Stem cell-An undifferentiated cell that retains the ability to develop into any one of a variety of cell types.
Stem cells are undifferentiated precursor cells whose daughter cells can differentiate into more specialized cells.
Development-The process whereby undifferentiated embryotic cells replicate and differentiate into limbs, organ systems, and other body components of the fetus.
If the germ-cells are undifferentiated, the offspring may arise from many cells or from a single cell; the first type is (4) germinal budding, the second is (5) sporogony.
In individuals either of the male or female sex, germ-cells which are quite undifferentiated and neutral in character, become amoeboid, and wander into the endoderm.
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