Finding the probability of "color-blind boys" and "color-blind boys" often appears in the probability calculation of sex-linked inheritance in the fifth chapter of senior high school biology. Students often mistakenly think that the probability of the two is the same, and there is no difference. Let's talk about how to analyze the probability of both. From the perspective of Chinese grammar, "boy color blindness" is a subject-predicate sentence, and the complete sentence is "boy color blindness"; "Color-blind boy" is a radical phrase, and both of them state the probability of "color blindness in boys", so the probability of "color blindness in boys" is the same. This kind of understanding and judgment leads to mistakes, and the essence of probability is the comprehensive knowledge combining mathematical theory with biological genetic law. "Boy color blindness" refers to how many boys suffer from color blindness. That is to say, "how many boys in the future are color blind", regardless of the gender ratio1:1; "Color-blind boys" refers to the number of boys suffering from color blindness in their offspring. The ratio of male to female is 1: 1. In order to illustrate the probability of "color blindness in boys" and "color blindness in boys", here are some examples: a couple with normal phenotype gave birth to a color-blind boy. What are the chances of having another color-blind boy? What are the chances of giving birth to another color-blind boy? Solution: According to the meaning of the question, we can deduce the parents' genotype (as shown below), deduce the possible genotypes of offspring according to the parents' genotype, and then determine the probability of color blindness of boys and boys according to the genotypes. Analysis: According to the diagram, only boys are color blind and girls are normal. The so-called probability means that the probability of "Xb" and "Y" meeting at each fertilization is 1/4, and the probability of giving birth to a "color-blind boy" is 1/4. For example, what are the chances of having "color-blind boys"? The question is about boys, so regardless of the sex ratio, the probability that Y meets Xb is 1/2. Example 2: A couple with normal phenotype gave birth to a son with albinism and color blindness. What are the chances that they will have another "phenotypically normal son"? What are the chances of another "son with normal phenotype"? Solution: According to the meaning of the question, it can be concluded that the genotype of parents is 1. The probability of "a son with normal phenotype" is similar to that of "a boy with color blindness". So the probability of "phenotype normal son" is 3/ 16. 2. The probability of "normal son phenotype" is similar to that of "boy color blindness". So the probability of "normal son phenotype" is 3/8.