Nondisjunction

Definition

Nondisjunction occurs when chromosomes fail to separate properly during meiosis, resulting in gametes with an abnormal number of chromosomes.

Analogy

Picture nondisjunction as if you're dividing cookies evenly among your friends. If you make a mistake and give someone too many or too few cookies, it's not fair – just as it's problematic for cells if they have too many or too few chromosomes.

Related terms

Trisomy 21 (Down Syndrome): A condition caused by nondisjunction where an individual has three copies of chromosome 21 instead of two. It’s like getting an extra cookie – sounds fun initially but can lead to complications.

Monosomy: This is when a cell has only one copy of a chromosome instead of the usual pair. It's like missing a cookie – you're left wanting more.

Polyploidy: A condition where an organism has more than two complete sets of chromosomes due to nondisjunction. Imagine having multiple boxes of cookies instead of just one.