Cell Division and the Cell Cycle

A set of practice vocabulary flashcards covering the cell cycle, mitosis, and meiosis based on lecture notes.

Cell Cycle

A regulated series of events in a cell's life that involves cell growth, DNA replication, and cell division, divided into $3$ phases: Interphase, M Phase, and Cytokinesis.

Interphase

The longest phase of the cell cycle where the cell prepares for division; it is divided into three sub-phases: G1, S, and G2.

G1 Phase (Gap 1 Phase)

The phase where the cell grows in size, carries out its normal functions, and prepares for DNA replication to ensure readiness for synthesis.

S Phase (Synthesis)

The events of the cell cycle where DNA replication takes place and the cell's entire genome is accurately duplicated.

G2 Phase (Gap 2)

The final preparation and quality control stage before cell division where the cell synthesizes proteins and checks that DNA has been accurately copied.

G0 Phase (Quiescent Phase)

The resting or non-dividing state where a cell exits the cell cycle; some cells, like nerve and heart cells, may remain in this phase permanently.

G1 Checkpoint

A critical point that assesses factors such as cell size, nutrient availability, and DNA damage before allowing the cycle to proceed.

G2 Checkpoint

A checkpoint that confirms DNA replication has occurred accurately and that the cell is ready for division.

M Checkpoint (Spindle Checkpoint)

A control stage that ensures all chromosomes are correctly aligned and attached to the spindle fibers before cell division occurs.

Mitosis

A nuclear division process in body cells where a single cell divides to produce two genetically identical daughter cells with the same number of chromosomes as the parent.

Somatic cells

The body cells where the process of mitosis occurs to produce identical daughter cells.

Chromosome

An organized structure consisting of DNA tightly coiled around histone proteins that carries genetic material.

Haploid number

The number of chromosomes found in a human gamete, which is $23$.

Diploid number

The total number of chromosomes in a human somatic cell, which is $46$, consisting of $23$ pairs.

Kinetochore

A group of proteins located at the centromere of the chromosomes where spindle fibers attach during cell division.

Meiosis

A specialized cell division in sexually reproducing organisms that forms $4$ genetically distinct haploid gametes from diploid germ cells.

Homologous Chromosomes

Pairs of chromosomes of the same size and shape containing the same set of genes, with one member inherited from each parent.

Synapsis

The process during Prophase I where homologous chromosomes pair up.

Crossing Over

A process during Prophase I where homologous chromosomes exchange genetic material at specific points called chiasmata or chiasma.

Independent Assortment

The random and independent orientation of homologous pairs during Metaphase I, allowing for different combinations of maternal and paternal chromosomes.