Question

[Melly1657]

A female who does not carry the color blindness allel has children with a male who is color blond. What proportion of their children will be colorblind? all- 1/4-1/2-or 3/4

[Melly1657]

please help answer this question!

[LilKim]

your question is missing a few details… is this an X linked, Y linked, recessive or dominant inheritance?

[2Loula]

Colour Blindness is an X-linked recessive trait. If a female has normal vision, and to have colour-bind children, she would either have to be a carrier of the recessive gene, and/or be married to a colour blind male.

For example, a cross between a colour-blind male (XrY) and a normal vision woman who is a carrier (XRXr) could have four possible offspring combinations.

1. Colour-blind male(XrY) – 1/4 or 25%
2. Normal Vision Boy(XRY) – 1/4 or 25%
3. Colour-blind female(XrXr) – 1/4 or 25%
4. Normal Vision Female carrier (XRXr) – 1/4 or 25%

However, since it is a sex-linked disease carried on the X chromosome, if the female does not have the colour-blindness allele at all, there is no way any of her children will be colourblind (though any female daughters will be carriers).

I hope this helps.

[loveangel]

the female needs 2 allele to inherit the colorblindness or baldness, while the male only needs 1…

but if their offspring is a female, then there’s a possibility that the female offspring will be a carrier..

[loveangel]

there’s this process to find the answer, the cross pollination.

[Revenged]

quote Melly1657:

A female who does not carry the color blindness allel has children with a male who is color blond. What proportion of their children will be colorblind? all- 1/4-1/2-or 3/4

Colour blindness is a X-linked recessive condition…

In this case the parents alleles are:

Mother : XX (not a carrier) vs. Father: XcY (sufferer of disease)

Offspring with be:

2 x Female carriers (XcX)
2 x Normal Males (XY)

So none of your answers are correct… In this case, none of the children would be colour blind…

[Revenged]

quote 2Loula:

However, since it is a sex-linked disease carried on the X chromosome, if the female does not have the colour-blindness allele at all, there is no way any of her children will be colourblind (though any female daughters will be carriers).

Yes, exactly…

[Dr.Stein]

quote loveangel:

there’s this process to find the answer, the cross pollination.

Pollination? 😕

[Author]

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