When chromosomes fail to separate during meiosis, this is known asMultiple Choicecrossing over.nondisjunction.translocation.random separation.mitosis.

Break Down the Problem

1. Identify the context: The question is about a failure during meiosis.
2. List the provided options: crossing over, nondisjunction, translocation, random separation, mitosis.

Relevant Concepts

1. Meiosis: A type of cell division that results in four daughter cells with half the number of chromosomes of the parent cell.
2. Nondisjunction: A failure of homologous chromosomes or sister chromatids to separate properly during cell division.
3. Crossing Over: An exchange of genetic material between homologous chromosomes during meiosis.
4. Translocation: A segment of one chromosome breaks off and attaches to another chromosome.
5. Random Separation: Refers to the random distribution of maternal and paternal chromosomes to daughter cells, which occurs in meiosis but does not specifically denote failure.

Analysis and Detail

• The key concept related to the failure of chromosomes to separate during meiosis is called nondisjunction.
• Nondisjunction can lead to gametes with an abnormal number of chromosomes, which can result in conditions such as Down syndrome.

Verify and Summarize

• Reviewing the definitions of each option, the term directly related to the failure of chromosome separation is clearly defined as nondisjunction.

Final Answer

The correct answer is nondisjunction.