What are organisms called that possess identical genetic factors for a specific trait?

Which plant is used as a model system in the study of plant genetics?

What term did Mendel use for the factors that determine the traits he studied?

The genotype of a plant showing the dominant phenotype can be determined by

In the case of $PTC$ tasters and non-tasters in humans,$T$ represents the dominant allele and $t$ represents the recessive allele. Which of the following genotypes is unable to taste $PTC$?

Which of the following is considered as a recessive character of Mendel?