organisms that have two alleles for a particular trait
homozygous
Organisms that have two alleles for a particular trait are called diploid organisms. Diploid organisms have two sets of chromosomes, one set from each parent. Each chromosome in a diploid organism carries pairs of genes, known as alleles, which determine the traits of the organism. When genes carry two different alleles, the dominant allele is expressed while the recessive allele is not expressed. The dominant allele masks the recessive allele and determines the physical characteristics of the organism. However, the recessive allele can still be passed on to offspring and can be expressed if both alleles are recessive. In contrast, if an organism has two identical alleles for a specific trait, it is said to be homozygous for that trait. If the organism has two different alleles, it is said to be heterozygous for that trait. Understanding the concept of alleles is important in predicting how traits will be inherited and expressed in offspring.
More Answers:
Incomplete Dominance: When Alleles Mix to Produce Unique PhenotypesPunnet Squares: Predicting Genotypic Outcomes of Genetic Crosses
Genetics: The Genotype and Phenotype Ratios in the F2 Generation From a Cross Between a Tall and a Short Parent Plant.