Final answer:
An individual with multiple sets of chromosomes from the same species is termed polyploid, often leading to reproductive isolation or larger and more robust individuals in plants.
Step-by-step explanation:
An individual that has multiple sets of chromosomes from the same species is best described as polyploid. This condition occurs, for example, when an abnormal diploid egg is fertilized by a normal haploid sperm, resulting in a triploid zygote.
Polyploidy is common in plants and can result in individuals that are larger and more robust than their peers with a normal number of chromosome sets. Autopolyploidy is a type of polyploidy where an organism has two or more complete sets of chromosomes from its own species, often due to an error in meiosis, leading to inability to interbreed or reproductive isolation.