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A Level Biology: About the Genetics and Allele Dominance

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Hi everyone!! I would like to ask one question from the past year Paper 5. Here's the link, http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_w11_qp_53.pdf

It is question no. 2, section (a), part (ii), about cross 3 and 4.

I attempted the question and referred to the mark scheme, here's the link for mark scheme, http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_w11_ms_53.pdf

I could understand the part about cross 4, but when it says about "the idea of 1:1 ratio in each sex", I got startled. I tried the genetic diagram for both if the gene is sex-linked or non sex-linked, and the ratio of 'with tail' to 'without tail' I got is the same for both conditions (sex-linked or not).

So I need you guys to help figure it out. Thank you.
 
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