From an outside source I was able to find that tongue rolling is a dominant trait, unattached earlobes are dominant, straight thumbs are dominant, and widow's peaks are dominant. Using this information it is possible to predict what my family's genotypes are. Since tongue rolling is a dominant trait, and my mother, Pamela, cannot roll her tongue, she definitely has a homozygous recessive (tt) tongue-rolling gene. My father, Carl II, on the other hand, can roll his tongue, which opts for two possible options: he either has a homozygous dominant (TT) gene, or a heterozygous (Tt) gene. Since all of Pamela's and Carl II's children can roll their tongues, it is quite probable that Carl II has indeed a homozygous dominant tongue-rolling gene, as this punnett square shows.
Attached vs. unattached earlobes seemed to be the most controversial survey taken, therefore the following results may lack accuracy. Carl II, who has unattached earlobes, and Pamela, who has attached earlobes, produced three children with unattached earlobes and one child with attached earlobes. Since unattached earlobes are the dominant trait, Pamela definitely has the homologous recessive genotype (ee). Then we can predict that Carl has the heterozygous genotype, since most of his offspring have unattached earlobes, but one of them have attached. As for hitch hikers thumb, I concluded that both my parents have the homozygous recessive gene (hh), as well as all of us offspring. Straight thumbs are dominant, and therefore the offspring of a person who carried that gene would have a chance of having a straight thumb, even if the other parent was homozygous recessive. Out of four kids all of us have hitch hiker's thumb, therefore having homozygous recessive hitch hiker thumb genes. Although, there is still a chance that one of my parents are heterozygous.
Widows peak is a dominant gene. Carl II has a widow's peak, his wife does not, and neither do any of his children. This means that Carl II probably has the heterozygous widow's peak gene (Ww) and Pamela has the homozygous recessive gene along with the rest of her children (ww).
Next I compared my findings with my class results.
What I found the most interesting about this was that the dominant traits are not always the most common. For example, Widow's peak is a dominant gene, however less than half of our class have them.
