Most scientific questions are based off of theory.
Collagen is single most abundant body
This is refered to as the chemical symbol. It is derived from the Latin name for the element which is why some elements like potassium (K) and sodium (N) have symbols different from their name on the periodic table.
In this case, the black body colour is the dominant one. The white dog is homozygous recessive.
As the cross between the black female 2 and the white male results in all black pups. This means that the all the offsprings are heterozygotes and the Female 1 is homozygous recessive having a BB phenotype (where B codes for dominant allele).
As the cross between the black female and the white male results in four white and three black pups. This means that the all the black offsprings are heterozygotes, and the white ones are homozygous recessive and the Female 2 have a dominant and 1 recessive gene, and is a hetrozygotezygous recessive having a Bb phenotype (where B codes for dominant allele and b codes for recessive allele).
