When two alleles are different for a particular gene, the organism is said to be?

When two alleles for a particular gene are different, the organism is described as heterozygous. This term is derived from the prefix "hetero-" which means "different." Heterozygous organisms possess two different alleles for a specific gene, which can result in a phenotype that is influenced by the relationship between those alleles, such as dominance and recessiveness.

For example, if one allele is dominant and the other is recessive, the dominant trait will typically be expressed in the phenotype of the organism. This genetic makeup plays a crucial role in the inheritance of traits and contributes to the genetic variation within a population.

In contrast, when an organism is homozygous, it has two identical alleles for a particular gene. The term "hybrid" often refers more broadly to offspring resulting from the combination of different species or varieties, but in genetics, it is sometimes used to denote heterozygous individuals as well. Understanding the differences between these terms is vital in genetics and Mendelian principles.