Dominant and recessive traits.
The dominant feature is dark hair color in humans, the recessive feature is light color. The phenotype will be divided as follows: AA for dark hair, aa both genes will give light hair, Aa genes will give dark hair, because the gene for dark hair is dominant. Children of the Aa genotype may have blonde hair, if the other parent has aa, will have aa or Aa, and dark-haired, if the child will have the Aa genotype when crossed. The children of an AA parent will be all dark-haired.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.