Answer:
'Genotype determinants' are just another set of words to describe alleles, because an allele is what determines your genes.
An allele is basically an alternative forms of a gene. Humans have 2 forms (2 alleles) for each gene (except in sex cells) one from your mom, one from your dad.
The allele occupies a fixed position (locus) on the chromosome and, depending on whether or not it is dominant or recessive, it determines the phenotypes- or how the gene will be physically expressed.
A Example of recessive alleles:
widows peak- you need two 'widows peak' alleles to have that feature physically expressed.
If you have 1 widows peak allele and another for 'no widows peak' then the dominant form will be expressed, in this case it means you will not have a widows peak.