Cell Divison

Vocabulary flashcards covering key terms and definitions related to the cell cycle, interphase stages, mitosis, and cell division control.

Zygote

A single-celled fertilized egg that develops into a multicellular human being.

Cyclins

Regulatory proteins that signal a cell when to begin and stop division.

Cancer

A disease resulting when cells lose control of the cell cycle and divide uncontrollably.

Cell Cycle

An ordered series of events of growth, DNA replication, and division in a cell.

Interphase

The non-dividing phase of the cell cycle devoted to growth and normal metabolism.

Cell Division

The stage of the cell cycle in which the cell actually separates into two daughter cells.

G1 Phase

First gap phase of interphase; cell grows and synthesizes RNA, proteins, and organelles.

S Phase

Synthesis phase of interphase when DNA and chromosomes are duplicated.

G2 Phase

Second gap phase; cell continues growth and prepares the machinery for mitosis.

G0 Phase

Quiescent stage where cells exit the cycle and do not prepare for DNA replication.

Somatic Cell

Any body cell except a sex cell; possesses a diploid (2n) chromosome number.

Sex Cell (Gamete)

Reproductive cell with a haploid (n) chromosome number; produced by meiosis.

Diploid (2n)

A cell containing two sets of chromosomes, one from each parent.

Haploid (n)

A cell containing one set of chromosomes.

Mitosis

Division of a somatic cell producing two genetically identical daughter cells.

Karyokinesis

Division of the cell nucleus during mitosis.

Cytokinesis

Division of the cytoplasm resulting in two separate daughter cells.

Prophase

First stage of mitosis where chromatin condenses and the spindle apparatus begins to form.

Metaphase

Stage of mitosis when doubled chromosomes align at the cell equator.

Anaphase

Mitotic stage where sister chromatids separate and move toward opposite poles.

Telophase

Final mitotic stage; nuclear membranes re-form and chromosomes decondense.

Sister Chromatids

Identical halves of a duplicated chromosome connected by a centromere.

Centromere

Region where sister chromatids are attached and spindle fibers connect.

Centrioles

Cylindrical organelles in animal cells that organize spindle fibers.

Spindle Fibers

Microtubules that attach to centromeres and move chromosomes during mitosis.

Asters

Star-shaped microtubule arrays around centrioles during prophase.

Cleavage Furrow

Indentation that begins cytokinesis in animal cells.

Cell Plate

Structure forming across a dividing plant cell that develops into the cell wall.

Chromatin

DNA-protein complex existing as long thin fibers during interphase.

Histones

Proteins around which DNA winds to form nucleosomes; synthesized in S phase.

Apical Meristem

Region in plant roots or shoots where rapid cell division occurs.

Quiescent Stage

Another term for G0 phase; a non-dividing resting state.

Karyotype

The number and visual appearance of chromosomes in a cell (context: karyokinesis).

Chromosome

A DNA molecule with associated proteins, visible during cell division.

Growth and Development

Purpose of cell division allowing organisms to increase cell number, not cell size.

Repair

Replacement of old, dead, or damaged cells through cell division.

Cyclin-Dependent Kinases (CDKs)

Enzymes that, with cyclins, phosphorylate target proteins to progress the cell cycle.

Kinetochore

Protein structure on a centromere where spindle fibers attach.

Oncogene

Mutated gene that can cause uncontrolled cell division leading to cancer.

Mitotic Rate

Frequency with which a population of cells completes the cell cycle.