Useful english dictionary. 2012.
sperm-aster — Cytocentrum with astral rays in the cytoplasm of an inseminated ovum; it is brought in by the penetrating spermatozoon and evolves into the mitotic spindle of the first cleavage division. [sperm + G. aster, a star (as … Medical dictionary
sperm aster — the centriole, with astral microtubules, that precedes the male pronucleus during fertilization … Medical dictionary
sperm center — noun or sperm centrosome : a sperm aster presumably derived from the middlepiece of the fertilizing sperm : the aster of the first zygotic division … Useful english dictionary
aster — SYN: astrosphere. [Mod. L. fr. G. a., a star] sperm a. sperm a.. * * * as·ter as tər n a system of gelated cytoplasmic rays arranged radially about a centriole at either end of the mitotic or meiotic spindle called also cytaster * * * n. a star… … Medical dictionary
reproductive system, plant — Introduction any of the systems, sexual or asexual, by which plants reproduce. In plants, as in animals, the end result of reproduction is the continuation of a given species, and the ability to reproduce is, therefore, rather conservative … Universalium
angiosperm — /an jee euh sperrm /, n. Bot. a plant having its seeds enclosed in an ovary; a flowering plant. Cf. gymnosperm. [ANGIO + SPERM] * * * ▪ plant Introduction any member of the more than 300,000 species of flowering plants (division Anthophyta) … Universalium
homopteran — /heuh mop teuhr euhn, hoh /, adj. 1. homopterous. n. 2. a homopterous insect. [1835 45; see HOMOPTEROUS, AN] * * * ▪ insect order Introduction any of more than 32,000 species of sucking insects, the members of which exhibit considerable… … Universalium
Meiosis — Not to be confused with miosis, mitosis, or myositis. For the figure of speech, see meiosis (figure of speech). Events involving meiosis, showing chromosomal crossover Meiosis (pronounced /maɪˈoʊsɨs/&# … Wikipedia
Cleavage (embryo) — In embryology, cleavage is the division of cells in the early embryo. The zygotes of many species undergo rapid cell cycles with no significant growth, producing a cluster of cells the same size as the original zygote. The different cells derived … Wikipedia
Monarch (butterfly) — Monarch Female Male … Wikipedia
