Final answer:
The term for having two different alleles for a trait is heterozygous, such as Tt in pea plants for height, where T is dominant for tallness and t is recessive for shortness.
Step-by-step explanation:
The term for having two different types of alleles for a particular trait is heterozygous. When an organism has one dominant and one recessive allele for a trait, it is considered heterozygous, for example, Tt represents a heterozygous genotype for height in pea plants, where 'T' indicates the dominant tall allele and 't' the recessive short allele.
In the case of Mendel's pea plants, a heterozygous pea plant (Tt) is tall, manifesting the dominant trait, and is phenotypically indistinguishable from a homozygous dominant pea plant (TT). It's important to note that the phenotypic expression of traits in heterozygous individuals follows the patterns discovered by Mendel, where the dominant allele's trait is expressed over the recessive allele. This foundational concept in genetics illustrates how alleles determine the inheritance of traits through simple dominant-recessive patterns or more complex patterns like codominance and incomplete dominance.
The term for having 2 different types of alleles for a particular trait is called heterozygous. In genetics, alleles are different versions of a gene that determine a specific trait. When an organism has two different alleles for a particular trait, it is said to be heterozygous. For example, in pea plants, the alleles for height include a dominant allele for tallness (T) and a recessive allele for shortness (t). If a pea plant has one T allele and one t allele, it is heterozygous for the trait of height.