Cladistics is based on the shared characteristics between organisms and their network of evolutionary relationships
It is known as stimulus or the plural form stimuli. It can be external or internal.
Its called a microscope slide
Well say the father had the genotype BB (dominant brown) and his mom had the genotype bb (recessive blonde).
If the boy got only one allele of brown hair and his phenotype is brown hair, then his genetic type is Bb
He is heterozygous (has two different alleles). But since brown hair is dominant, his phenotype is brown hair. But he does have the blonde recessive allele.
Hope this helps!