Theme 4-1 cell cycle

DNA Replication

The process by which a cell makes an exact copy of its DNA.

Mitosis

The regulated process of cell division in eukaryotic cells resulting in two identical daughter cells.

Binary Fission

A form of asexual reproduction in prokaryotic cells that involves the division of a single organism into two identical daughter cells.

Cell Cycle

The series of phases that a cell goes through leading to its division and replication, including interphase and the M phase.

Interphase

The phase of the cell cycle where the cell prepares for division, including growth and DNA replication.

G1 Phase

The first gap phase in the cell cycle where cells grow and prepare for DNA replication.

S Phase

The synthesis phase of the cell cycle where DNA replication occurs.

G2 Phase

The second gap phase before mitosis where final preparations for cell division are made.

Centrosomes

Cell structures that organize the microtubules during mitosis and are positioned at the poles of the dividing cell.

Sister Chromatids

Identical copies of a chromosome that are connected by a centromere and separated during mitosis.

Prometaphase

The stage of mitosis where the nuclear envelope breaks down and microtubules attach to kinetochores.

Metaphase Plate

The equatorial plane in the cell where chromosomes align during metaphase.

Anaphase

The stage of mitosis where sister chromatids are pulled apart to opposite poles of the cell.

Telophase

The final stage of mitosis where two new nuclei form at opposite ends of the dividing cell.

Cytokinesis

The process that follows mitosis and results in the division of the cytoplasm, leading to two distinct daughter cells.

Cyclin

A regulatory protein that controls the progression of the cell cycle by activating cyclin-dependent kinases (CDKs).

Cyclin-Dependent Kinase (CDK)

Enzymes that, when activated by binding to cyclin, phosphorylate other proteins to regulate the cell cycle.

Checkpoints

Regulatory mechanisms in the cell cycle that ensure proper progression and check for errors or damage.

p53 Protein

A protein that acts as a checkpoint regulator by inhibiting cell cycle progression in response to DNA damage.

Kinetochore

A protein structure on the centromere where microtubules attach to pull sister chromatids apart during division.

Quiescent Stem Cells

Dormant stem cells that can be activated to divide and differentiate when needed.

Homologous Chromosomes

Pairs of chromosomes, one from each parent, that are similar in shape, size, and genetic content.