Topic 5) The Mitotic Cell Cycle (AS)

Mitosis

A process that ensures the production of two genetically identical daughter cells, crucial for growth, tissue repair, and asexual reproduction.

Interphase

The preparation phase of the cell cycle consisting of G₁ (cell growth), S (DNA replication), and G₂ (final preparations for division).

M Phase

The mitotic phase that includes mitosis (nuclear division) and cytokinesis (cytoplasmic division).

Prophase

The initial stage of mitosis where chromosomes condense and become visible while the nuclear envelope begins to break down.

Metaphase

A stage of mitosis in which chromosomes align along the metaphase plate and spindle fibers attach to their centromeres.

Anaphase

The stage of mitosis where sister chromatids separate and move toward opposite poles of the cell.

Telophase

The stage of mitosis where nuclear envelopes reform around each set of chromosomes and chromosomes decondense.

Cytokinesis

The process of cytoplasmic division that results in the formation of two daughter cells.

Sister chromatids

Two identical copies of a chromosome joined together at the centromere.

Cohesin proteins

Proteins that hold sister chromatids together until they are separated during anaphase.

Spindle apparatus

A structure composed of microtubules that facilitates the segregation of chromosomes during cell division.

Aneuploidy

An abnormal number of chromosomes in a cell, often resulting from nondisjunction during mitosis.

Nondisjunction

An error in cell division where sister chromatids fail to separate properly, leading to abnormal chromosome numbers.

Significance of Mitosis

Maintains genetic consistency across generations, facilitates tissue growth and repair, and enables asexual reproduction in certain organisms.