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The indirect division of cells in which, prior to division of the cell protoplasm, complicated changes take place in the nucleus, attended with movement of the nuclear fibrils; -- opposed to karyostenosis. The nucleus becomes enlarged and convoluted, and finally the threads are separated into two groups which ultimatel…

on of the nucleus, without any changes in its structure, followed by division of the protoplasm of the karyostenotic mode of nuclear division.

One of certain very minute whitish or colorless granules occurring in the protoplasm of plants and supposed to be the nuclei around which starch granules will form.

Any of several minute protozoans of the genus Plasmodium (syn. Hæmatozoön) which in their adult condition live in the tissues of mosquitoes of the genus Anopheles (which see) and when transferred to the blood of man, by the bite of the mosquito, produce malaria. The young parasites, or sporozoites, enter the red blood…

tritive material brought to them by the blood, or by which they transform their cell protoplasm into simpler substances, which are fitted either for excretion or for some special purpose, as in the manufacture of the digestive ferments. Hence, metabolism may be either constructive (anabolism), or destructive (katabolis…

Those animals in which the protoplasmic mass, constituting the egg, is converted into a multitude of cells, which are metamorphosed into the tissues of the body. A central cavity is commonly developed, and the cells around it are at first arranged in two layers, -- the ectoderm and endoderm. The group comprises nearly…

A theoretical aggregation of molecules constituting a structural particle of protoplasm, capable of increase or diminution without change in chemical nature.

The denser part of the protoplasm of a cell.

the form of a monad; resembling a monad in having one or more filaments of vibratile protoplasm; as, monadiform young.

hat stage of development in which its form is simply that of a non-nucleated mass of protoplasm. It precedes the one- celled germ. So called from its likeness to a moner. Haeckel.

esembling mucin. The mucigenous basis is manufactured at the expense of the ordinary protoplasm of the cell. Foster.

The protoplasmic matter of which bacteria are composed.

A substance, present in the protoplasm of the retinal epithelium cells, and resembling, if not identical with, the substance (myelin) forming the medullary sheaths of nerve fibers.

agulation which takes place in rigor mortis; the clot formed in the coagulation of muscle plasma. See Muscle plasma, under Plasma.

re found on damp earth and decaying vegetable matter, and consist of naked masses of protoplasm, often of considerable size, which creep very slowly over the surface and ingest solid food. -- Myx`o*my*ce"tous (#), a.

dy, usually spheroidal, in a cell or a protozoan, distinguished from the surrounding protoplasm by a difference in refrangibility and in behavior towards chemical reagents. It is more or less protoplasmic, and consists of a clear fluid (achromatin) through which extends a network of fibers (chromatin) in which may be s…

nourishing; nutritious; nutrimental; alimental; as, nutritive food or berries. Nutritive plasma. (Biol.) See Idioplasma. -- Nutritive polyp (Zoöl.), any one of the zooids of a compound hydroid, or coral, which has a mouth and digestive cavity. -- Nu"tri*tive*ly, adv. -- Nu"tri*tive*ness, n.

An unfertilized, rounded mass of protoplasm, produced in an oögonium.

One of the protoplasmic cells which occur in the osteogenetic layer of the periosteum, and from or around which the matrix of the bone is developed; an osteoplast.

A more or less spherical and transparent mass of granular protoplasm, which by a process of multiplication and growth develops into a mass of cells, constituting a new individual like the parent; an egg, spore, germ, or germ cell. See Illust. of Mycropyle.