According to Mendel, how many alleles does each organism have for each trait?

Mendel's principles of inheritance indicate that each organism carries two alleles for each trait, one inherited from each parent. This concept is central to Mendelian genetics and is foundational in understanding how traits and characteristics are passed from one generation to the next. The presence of two alleles allows for the possibility of dominant and recessive interactions, leading to variations in phenotypes. For instance, if one allele is dominant over the other, only the dominant phenotype may be expressed in the organism. This fundamental idea helps explain genetic diversity and inheritance patterns observed in offspring.