Meiosis: Processes, Errors, and Genetic Diversity

Meiosis

Cell division producing four genetically distinct daughter cells.

Gametes

Haploid cells formed during meiosis for reproduction.

Crossing Over

Exchange of chromosomal segments between non-sister chromatids.

Independent Assortment

Random distribution of homologous chromosomes into daughter cells.

Nondisjunction

Failure of chromosomes to separate properly during cell division.

Aneuploidy

Abnormal number of chromosomes in a cell.

Monosomy

Loss of one chromosome from a pair.

Trisomy

Gain of an extra chromosome in addition to pairs.

Down Syndrome

Trisomy 21, caused by maternal nondisjunction.

Klinefelter Syndrome

XXY condition, often due to paternal nondisjunction.

Jacob's Syndrome

47,XYY male, typically normal appearance and fertility.

Karyotype

Display of all chromosomes in a somatic cell.

Sister Chromatids

Identical DNA molecules from a single DNA molecule.

Homologous Chromosomes

Pairs of chromosomes, one maternal and one paternal.

Genetic Recombination

Creation of new allele combinations through DNA exchange.

Prophase 1

Stage of meiosis where crossing over occurs.

Metaphase 1

Stage of meiosis where independent assortment occurs.

Metaphase 2

Second meiotic division stage with independent assortment.

Oocytes

Female gametes, more prone to meiosis errors.

Turner Syndrome

Monosomy of X chromosome, affects female development.

Fertilization

Union of sperm and egg, leading to genetic diversity.

Genetic Diversity Factors

Crossing over, independent assortment, and fertilization randomness.

Chromosomal Segments

Parts of chromosomes exchanged during crossing over.