Meiosis and Genetic Diversity

Flashcards covering key terms and concepts related to meiosis and genetic diversity.

Meiosis

A type of cell division that produces gametes, resulting in haploid cells from diploid cells.

Diploid

Cells that contain two complete sets of chromosomes, one from each parent; symbol is 2n.

Haploid

Cells that contain half the normal number of chromosomes; symbol is n.

Gametes

Sex cells (sperm and ova) that are haploid and involved in sexual reproduction.

Fertilization

The fusion of a sperm and egg to form a zygote.

Homologous Chromosomes

Pairs of chromosomes that are similar in shape and size and carry genes for the same traits.

Karyotype

A method of organizing chromosomes of a cell by number, size, and type.

Crossing Over

The exchange of segments between non-sister chromatids that occurs during prophase I, increasing genetic variation.

Independent Assortment

The random orientation of homologous chromosome pairs during metaphase I, leading to genetic variation.

Sister Chromatids

Identical copies of a single chromosome that are connected at the centromere.

Polar Bodies

Small cells produced during oogenesis that typically do not develop into ova.

Zygote

The fertilized egg that results from the fusion of a sperm and an egg.

Prophase I

The longest and most complex phase of meiosis I where homologous chromosomes pair up and exchange genetic material.

Metaphase I

The phase of meiosis I where tetrads align on the metaphase plate.

Anaphase I

The phase where homologous chromosomes are separated and pulled to opposite poles of the cell.

Telophase I

The phase of meiosis I where two haploid daughter cells are formed.

Meiosis II

A second meiotic division without preceding DNA replication that produces four haploid cells.

Gene Linkage

The phenomenon where genes that are inherited together are considered linked, affecting inheritance patterns.

Gene Maps

Diagrams that show the relative positions of genes on chromosomes based on the rates of crossing over.

Variation

Genetic differences that enhance survival and reproduction, often resulting from crossing over, independent assortment, and random fertilization.