Cell Cycle & DNA Replication

Cell cycle

series of events in which a cell grows, prepares for division, and divides to form two daughter cells

Nucleolus

Found inside the nucleus and produces ribosomes

Nuclear envelope/membrane

layer of two membranes that surrounds the nucleus of a cell

Chromosome

Condensed structure of DNA in preparation for cell division

Chromatin

Unravelled condensed structure of DNA for packaging within nucleus

Chromatid

one of two identical "sister" parts of a duplicated chromosome

Interphase

Cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

Somatic cell

any cell of a living organism other than the reproductive cells.

Gametes

reproductive cells

S Phase

DNA replication

G0 phase

A nondividing state occupied by cells that have left the cell cycle, sometimes reversibly.

G1 phase

The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins.

G2 phase

The second growth phase of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs.

Helicase

An enzyme that untwists the double helix of DNA at the replication forks.

DNA Polymerase

Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

Replication Fork

A Y-shaped region on a replicating DNA molecule where new strands are growing.

DNA ligase

enzyme that chemically links DNA fragments together

semi-conservative replication

in each new DNA double helix, one strand is from the original molecule, and one strand is new