What children will be born in a family to a curly-haired brunette heterozygous and straight-haired blonde?

As a rule, curly hair is dominant over straight hair. Let’s designate the gene that causes the development of curly hair as K, then the gene for straight hair will be designated as k.

As a rule, dark hair is dominant over light hair. Let’s designate the gene for light hair as l, then the gene that determines the development of dark hair will be L.

A heterozygous curly brunette will be written, according to the introduced designations, as KkLl. It will produce four types of sperm – kl, KL, Kl, kL.

A blonde with straight hair will be kkll, because the homozygosity of the genotype is a condition under which these traits, belonging to the recessive category, have the opportunity to be phenotypically realized. Such a woman will produce eggs of the same type – kl.

The possible offspring of this married couple will include the following options:

children with light straight hair (kkll) – 25%;

children with dark curly hair (KkLl) – 25%;

children with light curly hair (KK ll) – 25%;

children with dark straight hair (kkLl) – 25%.



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