A condition in which an organism has extra sets of chromosomes because a complete set of chromosomes failed to separate during meiosis (e.g., 3N or 4N) is called?

A condition in which an organism has extra sets of chromosomes because a complete set of chromosomes failed to separate during meiosis (e.g., 3N or 4N) is called?

• A. Polyploidy
• B. Trisomy
• C. Duplication chromosomal mutation
• D. Inversion chromosomal mutation

Answer: (A)

Polyploidy refers to having more than two complete sets of chromosomes. This occurs when a full set of chromosomes fails to separate during cell division, such as meiosis, leading to gametes or cells with extra genome copies. When fertilization combines a normal set with an extra set, or when a cell doubles its entire genome, the organism can end up with 3N (triploid), 4N (tetraploid), or higher levels. This is different from having a single extra chromosome (trisomy), which is aneuploid and involves only one chromosome being present in an extra copy. It’s also distinct from duplications (repeating a chromosome segment) or inversions (a segment flipped within a chromosome). So, the condition described—extra whole chromosome sets like 3N or 4N—is polyploidy.

Polyploidy refers to having more than two complete sets of chromosomes. This occurs when a full set of chromosomes fails to separate during cell division, such as meiosis, leading to gametes or cells with extra genome copies. When fertilization combines a normal set with an extra set, or when a cell doubles its entire genome, the organism can end up with 3N (triploid), 4N (tetraploid), or higher levels. This is different from having a single extra chromosome (trisomy), which is aneuploid and involves only one chromosome being present in an extra copy. It’s also distinct from duplications (repeating a chromosome segment) or inversions (a segment flipped within a chromosome). So, the condition described—extra whole chromosome sets like 3N or 4N—is polyploidy.