from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The mass of cytoplasm surrounding the centriole in a centrosome.
- n. The central core of the earth. Also called barysphere.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The cytoplasm surrounding the centriole of a centrosome.
- n. barysphere
from the GNU version of the Collaborative International Dictionary of English
- n. The nucleus or central part of the earth, forming most of its mass; -- disting. from
lithosphere, hydrosphere, etc.
- n. The central mass of an aster from which the rays extend and within which the centrosome lies when present; the attraction sphere. The name has been used both as excluding and including the centrosome, and also to designate a modified mass of protoplasm about a centrosome whether aster rays are developed or not.
from The Century Dictionary and Cyclopedia
- n. In cytology, a spherical, differentiated mass of cytoplasm surrounding the centrosome and constituting a pole of the karyokinetic spindle during cell-division. Also called attraction-sphere.
- n. The central or interior portion of the earth, beginning at a somewhat indefinite depth, and involving materials and pressures of which we have no actual experience; contrasted with the successive outer shells, lithosphere, hydrosphere, and atmosphere.
The protoplasm surrounding the centrosphere is frequently arranged in radiating fibrillar rows of granules, forming what is termed the attraction sphere.
In the middle of the centrosome is a minute body called the centriole, and surrounding this is a clear spherical mass known as the centrosphere.
2 Coincidently with or preceding these changes the centriole, which usually lies by the side of the nucleus, undergoes subdivision, and the two resulting centrioles, each surrounded by a centrosphere, are seen to be connected by a spindle of delicate achromatic fibers the achromatic spindle.