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1 莫让“配子”产生歧义(王宝华)贵刊2006年第5期《互动平台》栏目刊登了有关配子问题的讨论,笔者赞成其中的“习惯性说法应得到尊重”的观点。由于涉及“配子产生”的题目在高中生物教学中很常见,下面再举例作以讨论。例1 1个基因型为 AaBb 的精原细胞,按照自由组合规律,产生AB型配子的几率为 ( )A.0 B.25% C.50% D.75%讨论本题的解题思路主要有:思路1 减数第1次分裂时染色体及基因的分配方式只有两种:A 与 B 移向同一极;A 与 B 移向不同极。结果是,要么产生含 AB(ab)的配子,要么不产生含 AB 的配子而产生含 aB(Ab)的配子,所以产生 AB 型配子的几率是50%。也就是说,
1 Do not allow gamers to produce ambiguities (Wang Baohua) No.5, 2006, “Interactive Platform” published a discussion about gametes, and I agree that the “customary claims should be respected”. Since topics related to “gametogenesis” are common in high school biology teaching, the following is another example for discussion. Example 1 A genotype AaBb spermatogonia, according to the law of free combination, the probability of generating AB type gametes () A.0 B.25% C.50% D.75% Discussion The problem-solving ideas of this question are : Ideas 1 Chromosomes and genes are divided in the first division by subtraction: A and B move to the same pole; A and B move to different poles. As a result, gametes containing AB (ab) are either produced, or gametes containing AB are produced without producing aB (Ab) containing gametes, so the chances of producing AB-type gametes are 50%. In other words,