Allele for gray fur is A (dominant)
Allele for white fur is a (recessive)
Genotype of heterozygous is Aa (heterozygous is gray, because its allele is dominant)
If we cross two heterozygous
<span>Parents: Aa x Aa
</span> <span>F1: AA Aa Aa aa</span>
The ratio between phenotypes is 3:1 (gray:white)
<span>AA Aa Aa are with gray fur</span>
<span>aa is with white fur </span>
The development of the human embryo follows fertilization, and continues as fetal development. By the end of the tenth week of gestational age the embryo has acquired its basic form and is referred to as a fetus. The next period is that of fetal development where many organs become fully developed.
