Final answer:
The student's question concerns a trait that is dominant, meaning it does not skip generations and individuals with the trait have inherited at least one dominant allele from an affected parent, expressing the trait in the phenotype.
Step-by-step explanation:
The type of trait described in the question is indicative of a dominant trait. In terms of inheritance, a dominant trait is one where the trait is visible when at least one dominant allele is present. This means that the trait does not skip generations because the presence of a single dominant allele (homozygous dominant or heterozyous) in an individual is enough to express the trait. Therefore, affected individuals all have an affected parent because they must inherit at least one dominant allele to exhibit the trait.
Simple dominance in pedigrees shows that dominant traits appear in each generation, and any individual displaying the trait must have inherited a dominant allele from an affected parent. This concept is exemplified using Mendelian genetics, where traits like flower color or height can be traced through generations. Homozygosity refers to having two identical alleles, whereas heterozygosity refers to having one dominant and one recessive allele, with the dominant trait being phenotypically expressed in both cases.