An organism's underlying combination of alleles is its:

1. Two different words separate what an organism carries from what it shows. 2. An organism's underlying genetic makeup, consisting of both physically visible and non-expressed alleles, is called its genotype. 3. The phenotype is the visible result of that makeup. 4. Mendel's hybridisation experiments demonstrate the difference between the two. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 12 'Mendel's Experiments and Heredity', sections 12.1-12.3_