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    encolsed document with questions on. THANKS YOU!:yep:
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  1. File Type: doc genetic Q.doc (30.0 KB, 82 views)
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    do you need help for all parts?
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    for part 1: the son can’t inhert it because the allele is located on the X chromosome. This means that sperm that are X go on to be female(XX) and sperm that are Y go on to be male (XY). Y doesn’t have the allele so this means that the allele can only be passed on if the offspring is female.
    and im not sure about parts 2 + 3
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    (Original post by Summer24)
    encolsed document with questions on. THANKS YOU!:yep:
    What are your answers so far?
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    (Original post by Oracle_163)
    What are your answers so far?
    what do you mean?
    I need help on question 2 and 3. If you could help please. thanks
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    OK if you copied out the table correctly, wanted to let you know that the % of male sufferers being at 0.8% means that 0.8% of males in the population suffer from colour blindness, as do 0.7% of females. The occurrence of female sufferers is almost equal to the % of male sufferers assuming equal numbers of both. This condition occurs when females are homozygous recessive for the mutation involving colour blindness- this is because females are the homogametic sex possessing two X chromosomes, and as this trait is sex-linked, therefore females must inherit two X chromosomes which are mutant, ie X^n X^n vs X^NY and carrier females.

    For the third question, it could be because A) mutations causing red green colour blindness are more inherent in humans ie. it is easier to convert the normal phenotype for vision into one with red green colour blindness, B) there is a higher incidence of red green colour blindness alleles in the population as compared to haemophilia and DMD, and C) RG colour blindness does not phenotypically select as much against humans, ie. humans with haemophilia and DMD have a lesser chance of creating fertile viable offspring ie. having children, hence passing their traits on, while RG colour blindness is less of a factor. This leads to natural selection selecting against those with haemophilia and DMD resulting in lowered reproductive fitness of these groups. However this answer is leaning more towards evolution and diversity and is not such a strong answer as the first two as it is not as relevant...

    Hope you understand all the concepts mentioned above!
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    (Original post by Oracle_163)
    OK if you copied out the table correctly, wanted to let you know that the % of male sufferers being at 0.8% means that 0.8% of males in the population suffer from colour blindness, as do 0.7% of females. The occurrence of female sufferers is almost equal to the % of male sufferers assuming equal numbers of both. This condition occurs when females are homozygous recessive for the mutation involving colour blindness- this is because females are the homogametic sex possessing two X chromosomes, and as this trait is sex-linked, therefore females must inherit two X chromosomes which are mutant, ie X^n X^n vs X^NY and carrier females.

    For the third question, it could be because A) mutations causing red green colour blindness are more inherent in humans ie. it is easier to convert the normal phenotype for vision into one with red green colour blindness, B) there is a higher incidence of red green colour blindness alleles in the population as compared to haemophilia and DMD, and C) RG colour blindness does not phenotypically select as much against humans, ie. humans with haemophilia and DMD have a lesser chance of creating fertile viable offspring ie. having children, hence passing their traits on, while RG colour blindness is less of a factor. This leads to natural selection selecting against those with haemophilia and DMD resulting in lowered reproductive fitness of these groups. However this answer is leaning more towards evolution and diversity and is not such a strong answer as the first two as it is not as relevant...

    Hope you understand all the concepts mentioned above!
    oh thanks so much!
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    (Original post by Summer24)
    oh thanks so much!
    Always happy to help!
 
 
 
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