Aneuploidy is the condition that occurs when daughter cells are formed with unequal or abnormal number of chromosomes after mitosis and cell division.
Explanation:
Aneuploidy occurs when homologous chromosomes fail to segregate or rearrange leading to chromosomal nondisjunction. This condition leads to genetic mutations, giving rise to abnormal number chromosomes in the daughter cells, where (2n+1) or (2n-1) haploid daughter cells are formed instead of 2n chromosomes.
Trisomy is the aneuploidic condition caused when there is a third chromosomal (2n+1) copy instead of two copies, which has occurred in the given case leading to formation of daughter cells with 39 chromosomes instead of 38.
Aneuploidy disrupts cell function and can lead to organ malformation as in Down's syndrome, cell multiplication leading to cancers, etc due to disturbance of protein homeostasis.