Cell Division: Mitosis and Meiosis

Flashcards covering key concepts related to cell division, specifically mitosis and meiosis, and the generation of gametes.

Mitosis

A type of cell division that produces two diploid daughter cells that are genetically identical to the parent cell.

Meiosis

A type of cell division that produces four haploid daughter cells, each with a unique combination of chromosomes.

Gametes

Specialized sex cells produced by diploid organisms; they are haploid and carry only one copy of each chromosome.

Zygote

The resulting diploid cell formed when a sperm fertilizes an egg.

Sister Chromatids

Identical copies of a chromosome that are connected by a centromere, produced during DNA replication.

Homologous Chromosomes

Chromosome pairs, one from each parent, that are similar in shape, size, and genetic content.

Karyotype

A photograph or diagram of an individual's chromosomes, showing the number and structure of pairs.

Crossing Over

The exchange of genetic material between homologous chromosomes during prophase I of meiosis, increasing genetic diversity.

Bivalent (Tetrad)

A structure formed during meiosis when two homologous chromosomes pair up.

Cytokinesis

The process during cell division where the cytoplasm of a parental cell is divided into two daughter cells.

Independent Assortment

The random distribution of homologous chromosomes to daughter cells during meiosis.

Diploid

A cell that contains two complete sets of chromosomes, one from each parent (2n).

Haploid

A cell that contains only one set of chromosomes (n).

Prophase I

The first stage of meiosis I where homologous chromosomes pair up and crossing over occurs.

Anaphase I

The stage of meiosis I where the homologous chromosomes are pulled apart to opposite poles of the cell.

Telophase II

The final stage of meiosis II where sister chromatids reach the poles and the nuclear membrane re-forms.

Prophase II

The stage in meiosis II where the chromosomes condense and the nuclear envelope breaks down again.

Metaphase II

The stage in meiosis II where sister chromatids align along the metaphase plate.

Anaphase II

The stage in meiosis II where sister chromatids are separated and move toward opposite poles.

S Phase

The phase of the cell cycle where DNA replication occurs, resulting in sister chromatids.

Somatic Cells

Body cells that contain a full set of chromosomes (diploid).

Gamete Cells

Cells that undergo meiosis to produce sex cells (haploid).

Fraternal Twins

Twins that develop from two separate eggs fertilized by two separate sperm.

Identical Twins

Twins that develop from one egg fertilized by one sperm that splits into two embryos.