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    Mr and Mrs Donnelly are planning to start a family. however, Mr Donnelly is concerned that, as his late brother was diagnosed with Tay-Sachs disease, he may be a carrier of Tay-Sachs. Their GP explains how Mr Donnelly may carry the faulty gene for Tay-Sachs using a Punnett sqaure. Using Tt to represent a carrier, create a punnet square using the template below to explain to Mr Donnelly his chances of inherting the gene from his parents if both of them were carriers of the Tay-Sachs gene.

    Also explain your answer interms of Gamete formation and fertilisation( using the terms Haploid and diploid)

    In a seperate punnett square explain the possible outcomes for their children if Mr donnelly is Tay-Sachs carrier but his wife is not( explain your answer)


    Zahra and Toni are starting a family. They are using a friend’s donated sperm. Zahra can’t have children as she had a hysterectomy when she was younger. Toni has
    Huntingdon's, a dominant condition. Toni will be the egg donor and carry the baby. She does not know if she is Homozygous (HH) for the condition or heterozygous .(Hh). Using the punnet squares below explain all outcomes for their children if.

    (i) Toni is homozygous for the condition but the sperm donor is not.

    (ii) Toni is heterozygous for the condition but the sperm donor is not.

    when answering the question the terms phenotype, Genotype, homozygous and heterozygous, haploid and diploid need to be used for both questions.

    thank you!!!!!
    • Thread Starter

    anyone? i really need help with this question
    • Thread Starter



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