Biology STAAR (State of Texas Assessments of Academic Readiness) Practice Test

Nondisjunction during meiosis refers to the failure of chromosomes to separate properly during cell division. As a result, gametes produced can end up with an abnormal number of chromosomes. This can lead to conditions such as trisomy or monosomy in the resulting offspring, depending on whether there is an extra chromosome or a missing chromosome. For example, Down syndrome is a result of trisomy 21, where there are three copies of chromosome 21 instead of the normal two. This highlights how nondisjunction can have significant implications for genetic health and development in organisms.

The other options do not accurately represent the outcomes of nondisjunction. For instance, creating genetically identical cells typically occurs during mitosis, not meiosis, and does not relate to nondisjunction. Increased genetic diversity occurs through processes like crossing over and independent assortment during meiosis, which are not disrupted by nondisjunction. Lastly, nondisjunction does not eliminate recessive traits; rather, it can lead to an abnormal presence of chromosomes that may carry those traits.