Answer:
extra chromosomes are found in the sex cell
Step-by-step explanation:
Nondisjunction is a type of chromosome abnormality that leads to addition or loss of one or more whole chromosomes. Two homologous chromosomes fail to segregate and so move on into the same gamete cell. This results in half of the gamete containing two of the same chromosome while the other gamete have none. The individual will have three chromosomes that is normal homologous pair plus one extra chromosome.