共查询到20条相似文献,搜索用时 125 毫秒
1.
李国泰 《通化师范学院学报》2014,(2):45-47
本实验研究了果蝇白眼基因与小翅基因遗传距离的测定,选择白眼小翘的果蝇做为母本,母本必须为处女蝇,红眼长翅果蝇为父本,进行杂交培养,最终得到四种果蝇类型:红眼长翅果蝇,白眼小翅果蝇,红眼小翅果蝇,白眼长翅果蝇.并对果蝇白眼基因与小翅基因遗传距离进行了测定.结果表明果蝇的小翅基因与焦刚毛基因闻的重组率为24%,遗传距离为24cM. 相似文献
3.
选取纯种残翅果蝇和纯种小翅果蝇作亲本,分别进行正交和反交,F1自交,观察F2的翅型种类和性别.结果表明:(1)正交组合的F1果蝇无论雌雄皆为长翅,F2果蝇长翅∶小翅∶残翅接近于9∶3∶4,且小翅全为雄蝇.(2)反交组合的F1果蝇中,长翅全为雌蝇,小翅全为雄蝇,而F2果蝇的长翅∶小翅∶残翅接近于6∶6∶4,且各翅型雌雄蝇各占1/2.结论:果蝇翅型基因互作类型为隐性上位,正反交F2比例不同. 相似文献
4.
5.
6.
[目的]研究三丁基锡(Tributyltin,TBT)化合物对黑腹果蝇(Drosophila melanogaster)的致死效应和生殖阻碍作用。[方法]先进行TBT对黑腹果蝇的半致死剂量测定.再利用初次产卵时间、产卵数量和孵化率指标衡量TBT的生殖阻碍作用。[结果]TBT对野生型黑腹果蝇的24h、48h、72h和96hLc50分别是441μM、270μM、220μM和191μM。随着TBT浓度的升高。野生型、残翅型和白眼型果蝇的初次产卵时间均呈现推延现象,并且产卵数量和孵化率也呈现递减趋势。[结论]黑腹果蝇对TBT具有高耐受力。TBT具有显著的生殖阻碍作用,必须禁止TBT的使用以降低生态危害。 相似文献
7.
果蝇的性别是在性型结构和性基因数量的双重作用下 ,由有效数量大的X基因或Y基因决定性别 .各种性型的X基因与Y基因的有效数量的比率———性指数X/Y和Y/X :为 1.0时 ,发育为中性蝇 ;小于和等于 2 .0时 ,发育为异常雌蝇和异常雄蝇 ;等于和大于 2 .0时 ,发育为正常雌蝇和正常雄蝇 ;等于和大于 3 .0时 ,发育为超雌蝇和超雄蝇 相似文献
8.
果蝇白眼性状和人类红绿色盲一样是伴性遗传的经典实例,本文阐述伴性遗传的教学组织和科学方法训练。 相似文献
10.
11.
设定三个光照强度梯度,分别对三种基因型的果蝇进行三个时间梯度的光照培养,暗培养作对照,探究不同光照强度对果蝇发生量的影响.结果表明:在25℃时,6h/d和24h/d的光照时间内不同光照强度间果蝇的发生量差异极显著(P<0.01),12h/d不同强度的光照对果蝇发生量的影响差异不显著(P>0.05);不同基因型果蝇对光照的反应不同. 相似文献
12.
本实验初步研究万年油对红眼果蝇的7天急性毒性效应及对红眼雌性处女蝇的22天慢性毒性效应。采用野生型黑腹红眼果蝇,在其培养基中加入浓度分别为2%、20%的万年油,以2%的未加热食用油作为阴性对照组,计算平均寿命,最高平均寿命和死亡率,作为3个毒性指标。结果显示通过急性毒性试验计算出万年油的半数致死剂量为2.86%。慢性实验结果显示,与对照组相比,2%组3个毒性指标有显著性差异;20%万年油组3个毒性指标存在极显著性差异。结果说明万年油对红眼果蝇有较强毒性,且含油量越高,其毒性效应越大。 相似文献
13.
14.
15.
一种易于掌握的果蝇唾腺染色体制片方法 总被引:4,自引:0,他引:4
果蝇唾腺染色体制片技术是遗传学实验课中学生感觉困难较大的实验。用现行的实验方法不易得到理想的制片效果。本文总结了多年的工作经验,改进了果蝇唾腺染色体的制片方法,取得了良好效果。 相似文献
16.
周珊 《常熟理工学院学报》2007,21(7):98-101
美国黑人女作家托尼·莫里森的处女作《最蓝的眼睛》展现了一个黑人女孩为渴求一双白人所拥有的蓝眼睛而经历的悲惨遭遇。面对白人主流文化的强烈冲击,许多象故事主人公一样的黑人女性迷失在白人编织的理想关的神话里而无法自拔。然而,莫里森并非仅仅着重刻画白人理想关神话下的负面响应,同时也积极探讨了如何打破神话,在白人文化中保持黑人本色的有效途径。 相似文献
17.
Thomas C. Lorsbach Sherry Wilson Jason F. Reimer 《Contemporary educational psychology》1996,21(4):447-466
The present study examined whether language/learning disabled children have greater difficulty than nondisabled children suppressing information that becomes irrelevant during a sentence processing and memory task. During study trials, children were asked to predict and remember the terminal nouns for a series of sentences that highly constrained a terminal noun. For half of the study trials (fillers) the child's prediction was confirmed by presenting the child with the expected ending (e.g., “Butterflies fly by flapping their . . .wings.”). For the remaining study trials (critical trials), however, the sentence ending expected by the child was disconfirmed with a low-probability ending (target noun). Thus, when presented with the sentence, “We made a sandwich with peanut butter and . . . ,” the child's prediction (“jelly”) was disconfirmed with a different ending (“bananas”). Memory for the disconfirmed and target nouns of critical study trials were subsequently tested implicitly with a new sentence-completion task. In this case, memory for disconfirmed and target nouns that had been associated with individual study sentences were measured in terms of priming effects. The analysis of priming effects indicated that language/learning disabled children experienced greater difficulty than nondisabled children inhibiting the activation of irrelevant information (disconfirmed nouns) and sustaining the activation of relevant information (target nouns) during a verbal memory task. These results were discussed in terms of their implications for some of the memory and language difficulties of language/learning disabled children. 相似文献
18.
聂朝晖 《马钢职工大学学报》2013,(4):105-108
摘要:萨丽·摩根的《我的位置》通过她的家庭三代人的回忆记录,向所有人,包括不了解情况的土著人后代和很多对此一无所知的白人,揭露了土著黑人令人震惊的真实过去,使之几乎成与白人虚构的历史相对抗的另一部历史。由此说明,只有在这样的重述历史、重构历史中。土著人(包括萨丽-摩根及其他叙述者们)才能找到他们的位置,重新修复他们的土著性这个被白人政府强行割断的文化身份。作者通过分析主人公悲剧的原因,试图揭示出压制土著人的复杂主流白人文化和父权制作用的真实一面。 相似文献
19.
论我国残疾人无障碍权益保障法律制度的完善 总被引:1,自引:0,他引:1
随着我国社会与残疾人事业的发展,《残疾人保障法》的修改已提上议事日程。《残疾人保障法》的修改涉及诸多方面。其中,我国无障碍权益保障法律制度存在着明显的缺陷:对无障碍概念的界定过于狭窄,致使残疾人的权益保护不周。同时,我国的无障碍设施建设工作也存在诸多问题。因此,在修改《残疾人保障法》时,将“无障碍权益”单独设立一章加以规定,并增加相应的内容。同时应继续切实加强当前的无障碍设施建设和管理工作。 相似文献
20.
《Support for Learning》2004,19(4):162-168
Increased participation and success in education for disabled people will improve their social inclusion and benefit society in general. In this article Louca‐Mai Wilson discusses Disability Rights Commission research on education and its implications for policy and practice. Research findings are considered in relation to the need for the voices of young disabled people to be heard in research, policy and planning. A key finding was that young disabled people want to be regarded and treated as equal to their peers, with the same rights of access and educational opportunity. But schools and educational establishments vary in their willingness and capacity to address and remove existing access barriers. Inclusion is a key issue for many young disabled people; many feel isolated at school and college and often have lower expectations about their future than their non‐disabled peers. Inclusive practice and participation are key to ensuring that disability equality in education is achieved. 相似文献