Cell Cycle and Checkpoints - Vocabulary Flashcards

Vocabulary-style flashcards capturing key cell cycle concepts, phases, checkpoints, and cancer-related genes from the lecture notes.

Cell cycle

The series of events that prepare a cell for division and produce two new daughter cells; includes interphase and the mitotic (M) phase.

Interphase

The longest phase of the cell cycle, also called the resting phase; the cell is metabolically active and grows, replicates DNA, and prepares for division.

G1 phase (Growth 1)

Growth phase where the cell increases in size and synthesizes proteins to grow the cytosol.

S phase (Synthesis)

Phase in which DNA replication occurs, duplicating the genetic material prior to cell division.

G2 phase (Growth 2)

Final preparation phase before division; ensures DNA replication is complete.

M phase (Mitotic phase)

Phase where the cell divides, including mitosis and cytokinesis.

G0 phase

Resting state where the cell does not actively divide; some cells stay permanently in G0 while others may re-enter the cycle.

Binary fission

Prokaryotic cell division in which a parent cell splits into two identical daughter cells after DNA duplication.

Cytokinesis

Division of the cytoplasm resulting in two separate daughter cells after mitosis.

Checkpoints

Control points that verify whether key cellular activities are correctly completed at specific stages of the cell cycle.

G1 checkpoint

Checkpoint at the G1/S transition assessing cell size, nutrients, DNA integrity, and growth signals.

G2 checkpoint

Checkpoint at the G2/M transition assessing DNA integrity and whether DNA replication is complete.

Spindle checkpoint

Checkpoint at metaphase ensuring chromosomes are properly attached to spindle fibers and aligned before anaphase.

DNA replication

Process of copying the cell’s DNA during S phase to provide identical genetic material for daughter cells.

DNA integrity

Whether DNA is damaged; damage can pause the cell cycle for repair.

Apoptosis

Programmed cell death; a controlled process that eliminates damaged cells to prevent cancer.

Oncogene

Mutated or overactive proto-oncogene that promotes excessive cell division; acts like a gas pedal that sticks.

Proto-oncogene

Normal gene that codes for positive regulators of the cell cycle; acts like a gas pedal.

Tumor suppressor gene

Normal gene that slows cell division, repairs DNA, and promotes apoptosis; acts like a brake.

Cancer

Unregulated cell division due to breakdown of regulatory mechanisms, often involving changes in DNA.

Metaphase plate

Imaginary plane where chromosomes align during metaphase before separation.

Spindle fibers

Microtubule structures that attach to chromosomes to separate them during mitosis.

Chromosome alignment

Proper arrangement of chromosomes at the metaphase plate during metaphase.