A woman with normal vision XDXd, because her father is color blind – meaning his XdY genotype. A woman gets gamete Xd from him.
The woman’s husband is color blind – his XdY genotype.
We make a crossing scheme:
P (women) XDXd → (husband) XdY
A woman forms two types of gametes: XD; Xd
A man forms two types of gametes: Xd; Y
Possible genotypes and phenotypes of children:
HDX – a girl with normal vision (carrier)
XDY – a boy with normal vision
XdXd – color blind girl
XdY – color blind boy
The probability of having a color blind son is 25%
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.