Please explain this question experts

Dear student,
The question seems to lack information. Please divulge more details on it so that we can help you out. I have provided the general inheritance pattern of both hemophilia and color blindness.

Haemophilia is a sex-linked, recessive disorder. It is carried on X chromosomes, and like any other sex-linked disorder and follows crisscross inheritance, i.e., the trait is inherited from the homozygous mother to all the sons. Female offspring themselves remain unaffected but serve as a carrier of the disease. The pattern of inheritance can be explained with the help of the following cross:
  

                  Parent Phenotype                                   Haemophilic mother                                        Normal father
                                  
                  Parent Genotype                                    XhXh                                                                    XY

​                      Gametes                                        Xh             Xh                                                 X         Y

                   Progeny  Genotype                    XhX                  XhY                               XhX                   XhY
                 Progeny Phenotype          Carrier Female      Haemophilic male          Carrier female        ​Haemophilic male  

Colour blindness is X-linked recessive disorder because of which a person is not able to distinguish between some of the colours, which other people can recognise easily. In this disease, females become affected only when they carry a gene for colour blindness on both X chromosomes and become carrier when they contain affected gene on only one X chromosome. The male gets affected when it carry affected gene on its X chromosome. Hence, the genotype of affected female will be  XC XC , carrier female will be XCX and affected male will be XC Y. This can be depicted by the following cross:


Parents                           XC XC          X              XCY

​Gametes                             XC                           XC           Y

Offsprings                             XCXC                       XCY
​                                           Affected female       Affected male
                                                child                           child

Hope this clears your doubt.
Regards.
 

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