Question

In cats, black fur colour is caused by an X-linked allele: the other allele at this locus causes orange colour.. the heterozygote is tortoiseshell. what kinds of offring would you expect from the cross of a black female and an orange male?A) tortoiseshell female; tortoiseshell maleB) black female;orange maleC)orange female; orange maleD)tortoiseshell female; black maleE)orange female; black male

Answer 1

The kind of offspring to expect will be tortoiseshell female and black male.

Step-by-step explanation:

X linked alleles are normally passed from mother to sons and fathers to daughters.

In cats, black fur colour is caused by an X-linked allele: the other allele at this locus causes orange colour. the heterozygote is tortoiseshell.

Both the black fur colour and the orange fur colour will be inherited in the homozygous dominant form. Thus, we have:

Black female: XBXB Black male: XBY

orange female: XRXR orange male: XRY

The heterozygote: XBXR (female). No heterozygote male as the males only possess one X chromosomes. so they are either black or orange.

A cross between black female and an orange male gives:

XB XB

XR XBXR XBXR

Y XBY XBY

The kind of offspring to expect will be tortoiseshell female (an heterozygote) and black male.

Answer 2

D tortoiseshell female; black male

Step-by-step explanation:

Let the allele for black fur color be B, the alternate version (orange color) will be b while a Bb will appear tortoise shell in color.

Black female =
`X^BX^B`

Orange male =
`X^bY`

Crossing a black female with an orange male:

`X^BX^B` x
`X^bY`

Offspring

`X^BX^b` tortoise shell female

`X^BY` black male

`X^BX^b` tortoise shell female

`X^BY` black male.

All the females from the cross will be tortoise shell in appearance while all the males will be black.

The correct option is D.