Final answer:
Autopolyploidy is the condition where an organism has extra chromosome sets from its own species, resulting from a meiosis error. It is rare in animals but common in plants, where it often leads to larger and more robust individuals.
Step-by-step explanation:
The polyploid condition formed from the addition of one or more extra sets of chromosomes identical to the normal haploid complement of the same species is known as autopolyploidy. Autopolyploidy results from an error in meiosis where all the chromosomes move into one cell instead of separating, leading to cells or organisms with multiple complete sets of chromosomes from their own species. While polyploidy is rare in animals and can lead to sterility due to irregular meiosis, it is very common in the plant kingdom where polyploid plants are typically larger and more robust than their diploid counterparts.