- cleavage stages
-
initial stages in embryonic development where divisions of blastomeres are clearly marked. Usually the first through sixth cleavages (2-64 cells)
Dictionary of ichthyology. 2009.
Dictionary of ichthyology. 2009.
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
Carnegie stages — In embryology, Carnegie stages are a standardized system of 23 stages used to provide a unified developmental chronology of the vertebrate embryo.The stages are delineated through the development of structures, not by size or the number of days… … Wikipedia
animal development — Introduction the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals. Development thus occurs following the process by which a new generation of organisms is produced by … Universalium
Preimplantation genetic diagnosis — In medicine and (clinical) genetics preimplantation genetic diagnosis (PGD) (or also known as Embryo Screening) refers to procedures that are performed on embryos prior to implantation, sometimes even on oocytes prior to fertilization. PGD is… … Wikipedia
Sciara (genus) — Taxobox name = Sciara image width = 200px image caption = Sciara analis Schiner, 1864 regnum = Animalia phylum = Arthropoda subphylum = Hexapoda classis = Insecta subclassis = Pterygota infraclassis = Neoptera superordo = Endopterygota| ordo =… … Wikipedia
Maternal to zygotic transition — (MZT) is the stage in embryonic development during which development comes under the exclusive control of the zygotic genome. This requires both zygotic genome activation (ZGA) and degradation of maternal products. MZT is often thought to be… … Wikipedia
Sciara (gnat) — Sciara Sciara analis Schiner, 1864 Scientific classification Kingdom: Animalia … Wikipedia
Fossil embryos — Many fossils of the Ma|580|million year old Doushantuo formation have been interpreted as fossil embryos; embryos are also common throughout the Cambrian fossil record.PreservationTaphonomic studies indicate that embryos are preserved for longest … Wikipedia
Cryopreservation — of plant shoots. Open tank of liquid nitrogen behind … Wikipedia
blastula — the single layered, hollow ball of cells, the final product of cleavage stages in the embryo characterised by formation of the blastocoel … Dictionary of ichthyology