null adj. 1.无效力的,无束缚力的。 2.无效的,无用的,无益的;无价值的。 3.没特征[个性]的,没表情的。 4.〔罕用语〕不存在的,没有的;零(位)的;空的。 n. 【数学】零,零位;空;【无线电】零讯号,微弱讯号。 a null indicator 零示器;零位指示器。 the null method 衡消法。 null and void 【律】无效;失效(This check is null and void. 本支票无效)。 vt. 使无效。
mutation n. 1.变化,变异,更换;【生物学】突变;突变种;【语言学】母音变化;【音乐】(提琴的)变换把位;变声;【法律】让受。 2.(人世的)浮沉,盛衰。
Gene duplication is one of the most important factors that influence the evolution of genome size , the origination of novel gene , the genetic robustness against null mutations , the speciation , etc 摘要基因重复是基因通过不等交换、逆转录转座或全基因组重复等途径产生一个与原基因相似的基因或碱基序列。
Here we found g proteins also function in leaf , silique development and the yield of pollen microspore . we observed several traits or characters in the offsprings of gpal , agbl null mutation and gpa1 overexpression lines and found that the width of mutants " lamina is larger than that of the wild type , whereas the lamina length , petiole length and rosette diameter is smaller than the wild type , the ga overexpression lines is different from the mutants ; the silique length and the pedicel length is larger in mutants than that of wild type , and slightly smaller in overexpression lines than the control ; the morphometric character in silique tip is different in gpal from agbl mutants ; the yield of pollen microspore is larger in null mutants than wild type whereas smaller in overexpression lines 实验中我们跟踪观察了多代异三聚体g蛋白a亚基超表达转基因植株及a , p亚基缺失突变体的表型特征,发现突变体的叶片宽度大于对应的野生型,叶片长度,叶柄长度及莲座直径小于野生型,而超表达植株的上述某些特征与突变体相反; gp时突变体的长角果长度,花梗柄部长度大于野生型,而超表达ga植株种英则略小于对照; gpal突变体长角果尖端未出现咭乙i突变体的特征: gpal ,口gbl突变体花粉生成量大于野生型,而超表达ga植株的花粉生成量则略小于对照。