Cell Cycle and DNA Replication Vocabulary

Vocabulary flashcards covering key terms related to cell division, mitosis, DNA replication, and cell cycle regulation.

anaphase

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

cell cycle

The ordered sequence of events that a cell undergoes as it grows and divides into two daughter cells.

centromere

The specialized region of a chromosome where two sister chromatids are held together and where spindle fibers attach.

Chromatin

The complex of DNA and proteins (histones) that forms chromosomes within the nucleus of eukaryotic cells.

sister chromatids

Two identical copies of a single replicated chromosome that are joined together at the centromere.

S phase

The subphase of interphase during the cell cycle in which DNA is replicated (synthesized).

cytokinesis

The division of the cytoplasm following mitosis to produce two separate daughter cells.

G0

A non-dividing resting state of the cell cycle where cells have exited the active division cycle.

G1

The first gap phase of interphase in the cell cycle where the cell grows and synthesizes proteins necessary for DNA replication.

G2

The second gap phase of interphase following DNA replication where the cell prepares for mitosis and cell division.

mitotic spindle

A structure composed of microtubules that controls chromosome movement during mitosis.

mitosis

The process of nuclear division in eukaryotic cells that results in two genetically identical daughter nuclei.

Interphase

The period of the cell cycle between cell divisions, consisting of G1, S, and G2 phases, during which the cell grows and replicates its DNA.

telophase

The final stage of mitosis during which nucleoli reappear, nuclear envelopes reform around separated chromatin, and chromosomes decondense.

kinetochore

A protein structure on the centromere of a chromosome to which spindle microtubules attach during cell division.

Metaphase

The stage of mitosis in which duplicated chromosomes align along the center of the cell.

metaphase plate/equator

The imaginary plane perpendicular to the spindle fibers along which chromosomes line up during metaphase.

cell cycle regulation (check points)

Control mechanisms in eukaryotic cells that monitor and verify whether necessary processes at each phase of the cell cycle are completed before moving to the next phase.

Okazaki fragment

Short, newly synthesized DNA segments formed on the lagging template strand during DNA replication.

DNA polymerase

An enzyme that synthesizes new DNA strands by adding complementary nucleotides to a template strand during replication.

RNA primer

A short sequence of RNA nucleotides that serves as a starting point for DNA polymerase during DNA replication.

Lagging strand

The DNA strand synthesized discontinuously in short segments (Okazaki fragments) in the 5' to 3' direction away from the replication fork.

Leading strand

The DNA strand synthesized continuously in the 5' to 3' direction toward the replication fork.

replication origins

Specific nucleotide sequences in a genome where DNA replication is initiated.

Semiconservative model

The model of DNA replication in which each new double-stranded DNA molecule consists of one original parental strand and one newly synthesized strand.

Mutation

A permanent change in the nucleotide sequence of an organism's DNA.

Mutagen

A physical or chemical agent that causes genetic mutations by altering DNA sequences.

cancer

A disorder characterized by uncontrolled cell division and growth resulting from mutations that disrupt cell cycle regulation.

proto-oncogenes

Normal genes that promote cell growth and division, which can become cancer-causing oncogenes when mutated.

Telomerase

An enzyme that catalyzes the lengthening of telomeres in eukaryotic cells to prevent chromosome shortening during replication.

Telomere

A repetitive, non-coding DNA sequence located at the ends of eukaryotic chromosomes that protects them from degradation.

tumor suppressors

Genes that code for proteins that inhibit cell division, repair DNA errors, or trigger apoptosis to prevent tumor development.

Cyclins

A family of proteins that regulate the progression of the cell cycle by activating cyclin-dependent kinases.

Kinase

An enzyme that catalyzes the transfer of a phosphate group from ATP to a target protein, altering its activity.

cell-cycle arrest

A temporary or permanent stopping of the cell cycle, typically triggered by DNA damage or failed cell cycle checkpoints.