We know that height in humans is a polygenic trait because it has a lot of variation. The height gene is controlled by at minimum three genes with six different alleles. If all of these alleles are dominant for the tall gene you will be tall if you are dominant for the short gene you will be short if there is no clear dominance between the two genes you will fall somewhere in the middle.
An allele is dominant and heterzygote (Pp) when a dominant allele (P) is crossed with a recessive allele (p).
Explanation:
A dominant allele is the one with a particular dominant character or phenotype which dominates even though there are other alleles found.
A heterozygous allele results from two different alleles coding for a gene.
A heterozygous dominant allele (Pp) results from the crossing of a dominant allele (P) with a recessive allele due to complete masking of the recessive allele (p).
For example, when dominant brown eyes are crossed with recessive blue eyes, in a heterozygous dominant allele results in brown eyes and masks the recessive blue eyes.
If they live in a river, they would most likely need fins (to swim) and gills (to breathe under water)
Hope this helps!
Oceanic crust is thinner and denser than continental crust.
