|
| segmentation | (เซเมินเท'เชิน) n. การแบ่งออกเป็นส่วน (ตอน, ท่อน, ข้อ, ปล้อง, ซีก, เสี้ยว, ชั้น, กลีบ) , ส่วน, ตอน, การแบ่งเซลล์ |
| | | | | | | blastocoel | (n) the fluid-filled cavity inside a blastula, Syn. blastocele, cleavage cavity, segmentation cavity, blastocoele | cleavage | (n) (embryology) the repeated division of a fertilised ovum, Syn. segmentation | division | (n) the act of dividing or partitioning; separation by the creation of a boundary that divides or keeps apart, Syn. partition, segmentation, partitioning, sectionalisation, sectionalization |
| Desegmentation | n. (Anat.) The loss or obliteration of division into segments; as, a desegmentation of the body. [ 1913 Webster ] | Segmentation | n. The act or process of dividing into segments; specifically (Biol.), a self-division into segments as a result of growth; cell cleavage; cell multiplication; endogenous cell formation. [ 1913 Webster ] Segmentation cavity (Biol.), the cavity formed by the arrangement of the cells in segmentation or cleavage of the ovum; the cavity of the blastosphere. In the gastrula stage, the segmentation cavity in which the mesoblast is formed lies between the entoblast and ectoblast. See Illust. of Invagination. -- Segmentation nucleus (Biol.), the body formed by fusion of the male and female pronucleus in an impregnated ovum. See the Note under Pronucleus. -- Segmentation of the ovum, or Egg cleavage (Biol.), the process by which the embryos of all the higher plants and animals are derived from the germ cell. In the simplest case, that of small ova destitute of food yolk, the ovum or egg divides into two similar halves or segments (blastomeres), each of these again divides into two, and so on, thus giving rise to a mass of cells (mulberry mass, or morula), all equal and similar, from the growth and development of which the future animal is to be formed. This constitutes regular segmentation. Quite frequently, however, the equality and regularity of cleavage is interfered with by the presence of food yolk, from which results unequal segmentation. See Holoblastic, Meroblastic, Alecithal, Centrolecithal, Ectolecithal, and Ovum. -- Segmentation sphere (Biol.), the blastosphere, or morula. See Morula. [ 1913 Webster ]
|
| | | | |
add this word
You know the meaning of this word? click [add this word] to add this word to our database with its meaning, to impart your knowledge for the general benefit
Are you satisfied with the result?
Discussions | | |