In humans, color blindness is due to a recessive gene (c) located on the X chromosome, and normal color blindness is due to a dominant gene (C).
1) A man who is color blind marries a woman who is color blind. Determine what is the probability of birth in this marriage: a) a normal son; b) daughters with color blindness.
2) A normal woman with a color blind father marries a normal man. What is the likelihood that this family will have children with color blindness?
3) A normal woman whose father was color-blind marries a color-blind man. What is the probability of the birth of color-blind children in this family?
4) Husband and wife have normal vision, and their daughter is color blind. What are the genotypes of the parents?
5) A normal woman, whose father has normal color vision, and whose brother is color blind, gave birth to a son. What is the likelihood that he turns out to be color blind?
6) A man with color blindness marries a normal woman. They have two children – a son with color blindness and a daughter with normal color vision. Determine: a) the mother’s genotype; b) the probability of the birth of a color blind daughter in this family.
1) a) The probability of the birth of a normal son from the marriage of a color-blind man and a woman-carrier of color blindness 1/4;
b) the probability of the birth of a daughter with color blindness from the marriage of a color blind man and a woman carrier of color blindness 1/4;
2) the probability of having children with color blindness from the marriage of a woman with normal color vision, whose father suffered from color blindness, and a man with normal color vision 1/4;
3) the probability of the birth of color-blind children from the marriage of a woman with normal color vision, whose father was color-blind, and a color-blind man 1/2;
4) genotypes P: (women) ХСХС, (husband) XсY;
5) a) if a woman with normal color vision, having a father with normal color vision and a brother who is color blind, is homozygous, then the probability that her son will be color blind is 0;
b) if a woman with normal color vision, who has a father with normal color vision and a color blind brother, is heterozygous, then the probability that her son will be color blind is 1/2;
6) a) maternal genotype of CHS;
b) the probability of having a color blind daughter 1/4.
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