Chapter 12

Cell Division

The process by which a parent cell divides into two daughter cells

Chromosome

A DNA molecule with associated proteins that carries genetic information

Genome

The complete set of genetic material in a cell

Centromere

The region of a chromosome where sister chromatids are joined

Sister Chromatids

Identical copies of a chromosome connected at the centromere

Interphase

The phase of the cell cycle in which the cell grows and duplicates DNA (G1, S, G2)

G1 Phase

Cell growth and preparation for DNA replication

S Phase

DNA replication

G2 Phase

Preparation for mitosis, including synthesis of proteins and organelles

Mitotic Phase (M Phase)

The phase in which mitosis and cytokinesis occur

Prophase

Chromosomes condense, spindle fibers form, nuclear envelope begins to break down

Metaphase

Chromosomes align at the metaphase plate

Anaphase

Sister chromatids separate and move toward opposite poles

Telophase

Nuclear envelope reforms, chromosomes decondense

Cytokinesis

Division of the cytoplasm into two daughter cells

Checkpoints

Regulatory points in the cell cycle (G1, G2, M) that ensure proper division

G0

A non-dividing state for cells that have exited the cycle

MPF (Maturation Promoting Factor)

A protein complex that triggers the cell’s entry into mitosis

Cyclin

A protein that regulates the cell cycle by activating CDKs

CDK (Cyclin-Dependent Kinase)

A kinase activated by cyclin to phosphorylate target proteins

Growth Factors

Proteins that stimulate cell division

PDGF

Platelet-Derived Growth Factor, promotes cell division

Density-Dependent Inhibition

The cessation of cell division when cells reach a certain density

Anchorage Dependence

The requirement for cells to be attached to a substrate to divide

Abnormal Growth

Unregulated cell division, potentially leading to cancer

Mitosis Lab

Experiment to identify cell cycle stages and calculate expected values using chi-square