Chromosomal aberrations in embryos from overripe eggs☆
[摘要] OverripenessineggsofRanapipienswasobtainedbykeepingpostovulatoryfemalesatroomtemperatureanddelayingfertilization3–5days.InXenopuslaevissimilarresultswereattainedbydelayingovulation.About80crippledembryos,issuedfromoverripeeggsthatwereusedforchromosomalstudies,hadreachedprefeedingstagesrangingfrom20to24.Bythistimethemostseverelyabnormalindividualshadalreadydied,butalsothemajorityofthosestudiedwouldprobablynothavebeenabletosurviveuntilmetamorphosis.Somemalformedembryosstillhavenormalchromosomecomplements,butthemajorityshowdeviationswhichareclassifiedasmeiotic,ploidic,andcleavagetypes.Itisconcludedthatoverripenessoftheeggisanimportantcauseofchromosomalnondisjunctioninmeioticandinmitoticdivisions.Nodefiniterelationshipbetweenthetypeofchromosomaldeviationandthemorphologiccharacterofmalformationshasbeenestablished,sofar.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
