哈代-温伯格定律的遗传学教学需要厘清的问题

哈代-温伯格定律是群体遗传学的重要理论基石,也是现代生物进化论的基础。教学中,需要厘清哈代-温伯格定律的基本原理、种群基因频率和基因型频率估算的方法,以及微观进化的机制等几个问题;理解遗传平衡定律的理论和实践意义。     

哈代-温伯格平衡定律在高中生物学习中的应用

对哈代-温伯格平衡定律在高中生物学习中的应用进行了分析。     

巧用哈代-温伯格定律解析2015年相关高考试题

分析高中生物教材中有关哈代-温伯格定律的相关知识,并就如何巧用此定律解2015年几道相关高考试题进行介绍。     

利用哈代-温伯格定律,巧析伴性遗传特点

在伴X染色体遗传中,隐性遗传特点是男性患者多于女性患者;显性遗传是女性患者多于男性患者。很多生物学教师不知如何解释这种特点。实际上,该特点可以运用哈代-温伯格定律来进行解释。哈代-温伯格定律指出:在一个有性生殖的自然种群中,若符合以下5个条件,即种群大、种群中个体间的交配是随机的、没有突变发生、没有新基因加入、没有自然选择等,各等位基因的频率和等位基因的基因型频率在一代一代的遗传中是稳定不变的,或者说是保持着基因平衡。在伴性遗传中,哈代-温伯格定律又有其特殊性。假设一对等位B、b位于X染色体上,在整个人群中,假…     

从IBO试题谈哈代—温伯格定律

哈代—温伯格定律（Ｈａｒｄｙ－Ｗｅｉｎｂｅｒｇ）是ＩＢＯ考纲规定的竞赛内容之一,并且在连续９届ＩＢＯ理论试题中都以不同形式进行了考查。但是很多中学教师对此定律不太熟悉,希望获得更多的了解。本文通过对几道ＩＢＯ试题的解析,谈谈该定律及其应用。１．哈代—...     

例析遗传平衡定律与配子棋盘法的内在联系

遗传平衡定律又称哈代——温伯格定律,它的使用条件必须满足五个条件:(1)种群足够大;(2)种群间个体要能自由交配;(3)没有突变;(4)没有迁入迁出;(5)没有自由选择.     

精算还是估算?——哈代-温伯格定律的应用实例分析

<正>哈代-温伯格定律也叫遗传平衡定律,是群体遗传学的重要理论基石。在中学生物教学中,需要教师在理解遗传平衡定律基本原理的基础上,指导学生利用其对种群的基因频率和基因型频率进行计算。但学生在实际运用中,往往会出现一些理解和计算上的问题。下面列举两个常见的实例进行分析。例1某地区每10 000人中有一个白化病患者,求该地区一对正常夫妇生出一个白化病小孩的概率是多少?参考答案1/10 201解析白化病是常染色体隐性遗传病(设显性基因为A,隐性基因为a),由题干信息可知,其发病率约为:     

基因频率与基因型频率计算题型归纳与分析

<正>1基本概念和计算公式1.1基因频率:基因频率是某种基因在某个种群中出现的比例,是某基因总数占种群中该基因和其等位基因和的比例。其计算公式为:某基因频率(%)=(种群中某基因的总数)/(全部等位基因的个数)×100%1.2基因型频率种群中某种基因型在整个种群中所占的比例。其计算公式为:某基因频率(%)=(种群中某基因型的个体数)/(种群总的个体数)×100%1.3哈代-温伯格定律1.3.1定律理解遗传平衡指在一个极大的随机交配的种群中,在没有突变发生,没有自然选择和迁移的条件下,种群     

“哈迪-温伯格定律”应用例析

对"典型概率计算问题"这一高中生物学的重点和难点内容进行辨析,应用"哈迪-温伯格"定律化解难点,重点强调在应用中如何分析界定性状的范围问题。     

哈迪-温伯格定律在“自由交配”遗传题中的误用

<正>哈迪-温伯格定律在群体遗传学中非常重要,在理想状态下,各等位基因的频率在遗传中是稳定不变的,即保持着基因平衡,即在群体内各个个体间如果进行随机交配,群体将会保持平衡,不发生改变。计算类的遗传题是人教版新教材必修2《遗传与进化》第一章和第五章里的重点与难点,对学生来说,理解难度较大。下面以两道常见的“自由交配”遗传题为例,通过比较不同的解题方法(包括正确的与错误的)来分析在题目给定的条件下如何正确使用哈迪-温伯格定律解题,     

论考试中的猜测问题

考生在回答选择题时 ,对把握不透的题目进行猜测 ,在不同程度上影响考试结果的可信度。本文就猜测与校正问题进行讨论 ,并对鼓励猜测提出一些看法     

Alternative vocabularies in the test validity literature

Justification of testing practice involves moving from one state of knowledge about the test to another. Theories of test validity can (a) focus on the beginning of the process, (b) focus on the end or (c) encompass the entire process. Analyses of four case studies test and illustrate three claims: (a) restrictions on validity entail a supplement required to obtain justification from validity. (b) Rationales for restrictions assume particular contexts. (c) Claims can be translated between contrasting vocabularies. Implications for consumers of test validity theory include encouragement to focus on content instead of form and to write and read mindfully of the multiplicity of validity vocabularies. Implications for producers of test validity theory include encouragement to consider multiple reconstructions of a particular theory of test validity, clearly distinguish validity theories from validity definitions, and focus on contributing arguments that constrain possible theories rather than contributing definitions or broad frameworks.     

Fear appeals in the primary classroom: Effects on test anxiety and test grade

The present study investigated whether fear appeals used prior to a test increased self-reported test anxiety and had a detrimental effect on test scores. Forty primary school pupils were instructed for one week under a low threat condition under which no fear appeals were made and another week under a high threat condition in which fear appeals were made salient. An end-of-week test was given in both conditions. Pupils reported an increase in test anxiety related worrisome thoughts and autonomic reactions under the high threat condition, but not in off-task behaviours. Test scores were lower under the high threat condition, but were not attributable to the increases in test anxiety related thoughts and autonomic reactions. This study adds weight to the argument that fear appeals are a damaging classroom strategy, but the mechanism by which fear appeals are reducing test scores is not yet clear.     

A comparison of the peabody individual achievement test,the metropolitan achievement test,and the otis-lennon mental ability test

In order to clarify the concurrent validity of the Peabody Individual Achievement Test (PIAT) and the Metropolitan Achievement Test (MAT), product-moment correlations were computed for all subscores and total scores for 26 normal-range public school third-grade girls and boys. The reading comprehension subtests correlated.81, spelling.88, and PIAT Mathematics with MAT Total Math.64. Correlations were computed for the Otis-Lennon Mental Ability Test and the PIAT General Information subtest as.77, and the Otis-Lennon and the PIAT Total Test scores as.79. Concurrent validity of the PIAT with both tests is tentatively considered adequate except in the area of mathematics, in which the PIAT, relative to the MAT, appears to be reflecting ability to handle math concepts (.68) more accurately than math computation (.41) or math problem solving (.56). Correlations with IQ partialed out suggest the PIAT Total Test, and PIAT and MAT reading and spelling measures, are relatively uninfluenced by IQ variations, whereas with IQ held constant, the weak positive correlations between the PIAT and MAT math subtests became essentially random relationships.     

2020年高考理综卷生物学试题中科学推理能力考查的定量分析

作为科学思维的核心要素,科学推理能力在生物学学科核心素养的培养与考查中具有重要地位。本文以试题中考查的科学推理能力为切入点,对2020年高考全国Ⅰ、Ⅱ、Ⅲ卷以及浙江、天津、江苏、山东自主命题试卷中的生物学试题进行了定量分析。     

Positive reframing and the test performance of test anxious children

The present study tested whether the paradoxical technique of positive reframing, presented in the form of test instructions, could be used to reduce the cognitive experience of worry and thereby improve the arithmetic test performance of highly test anxious third-and fourth-grade children. Thirty high test anxious and thirty low test anxious children were assigned randomly to receive one of three types of instructions prior to taking an arithmetic word problem test: neutral instructions, reassuring instructions, and positive-reframing instructions, which encouraged the children to view worry as a positive attribute. The results indicated that the type of instructions given had no significant effect upon subsequent test performance. However, both high and low test anxious children who received positive reframing scored significantly higher on a state anxiety measure given post test. These findings suggest that, although positive reframing may have an emotional impact, it is ineffective in improving the arithmetic test performance of highly test anxious children.     

Learning the class test

European Journal of Psychology of Education - The class test is one of the important school practices which construct and convey to the pupils the predominant conception of ability and the related...     

英语专八短文改错题型的测试学效度研究

本文采用定量研究来分析2006年到2013年近八年的英语专八短文改错题型的效度。统计表明专八短文改错题有一定的表面效度,但是因为它的题型大部分停留在语法词汇层面的考查上,而语义的辨识和语境理解考查还欠缺,因此,短文内容效度不高,没有充分发挥一篇完整短文的作用。