first maturation division

См. также в других словарях:

• oocyte — The immature ovum. SYN: ovocyte. [G. oon, egg, + kytos, a hollow (cell)] primary o. an o. during its growth phase and before it completes the first maturation division. secondary o. an o. in which the first meiotic division i …   Medical dictionary

• Oogonium — A female ancestral germ cell that divides several times to give rise to an oocyte that, in turn, develops into an ovum (an egg). The second o in oogonium is pronounced separately from the first: o·o·gon·i·um. The word was created from the prefix… …   Medical dictionary

• primary oocyte — n a diploid oocyte that has not yet undergone meiosis * * * an oocyte that has begun but not completed the first maturation division; it is derived from an oogonium by differentiation near the time of birth …   Medical dictionary

• Life Sciences — ▪ 2009 Introduction Zoology       In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… …   Universalium

• plant development — Introduction       a multiphasic process in which two distinct forms succeed each other in alternating generations. One form, created by the union of sexual cells (gametes (gamete)), contains two sets of similar chromosomes (diploid). At sexual… …   Universalium

• Germ cell — Germ cells are progenitors of the gametes. These singled out cells move through the gut to the developing gonads and undergo mitotic proliferation followed by meiosis and differentiation into either eggs or sperm (mature gametes). Plants do not… …   Wikipedia

• Oogenesis — Oogenesis, ovogenesis or oögenesis (  /ˌoʊ …   Wikipedia

• human embryology — ▪ biology Introduction       the process encompassing the period from the formation of an embryo, through the development of a fetus, to birth.       The human body, like that of most animals, develops from a single cell produced by the union of… …   Universalium

• Oogenesis — The process of egg formation. The second o in oogenesis is pronounced separately from the first: o·o·gen·e·sis. The word was created from the prefix oo (Greek oon, egg) + genesis (the coming into being of something) = the coming into being of the …   Medical dictionary

• secondary oocyte — n an oocyte that is produced by division of a primary oocyte in the first meiotic division * * * an oocyte in the period between the first and second maturation division; it is derived from a primary oocyte shortly before ovulation by a division… …   Medical dictionary

• ootid — The nearly mature ovum after the first meiotic division has been completed and the second initiated; in most higher mammals, the second meiotic division is not completed unless fertilization occurs. [G. ootidion, a diminutive egg. See id (2)] * * …   Medical dictionary