An individual's and actual genetic make-up is called their genotype.

Here's a breakdown:

* Genotype: The specific combination of alleles (different versions of a gene) an individual possesses. This is the genetic blueprint.

* Phenotype: The observable physical and biochemical characteristics of an individual, determined by the genotype and environmental influences.

For example, someone might have the genotype "BB" for the gene that determines eye color. This genotype would result in the phenotype of brown eyes.