The cell cycle is the ordered sequence of events through which a cell grows, copies its DNA, and divides to produce daughter cells. This lesson introduces the cycle’s major phases and focuses on interphase, when a cell grows and prepares for division, as well as G₀, a state outside the active cycle.
The result is usually two genetically identical daughter cells. Nuclear division is also called karyokinesis. Interphase and karyokinesis can occur without cytokinesis; when the cytoplasm does not divide, a cell with multiple nuclei may result.
All flashcards
What is the cell cycle?
The ordered sequence of events involving cell growth, DNA replication, and cell division that usually produces two daughter cells.
What are the three stages of interphase?
G₁, S, and G₂: growth and resource accumulation, DNA replication, and final preparation for mitosis, respectively.
What is G₀?
A quiescent state outside the active cell cycle; cells may enter it temporarily or remain there long term.
What is cytokinesis?
Physical division of a cell’s cytoplasm into two daughter cells, usually completing cell division.
How can cell counts estimate time spent in a cell-cycle stage?
The fraction of sampled cells in a stage approximates the fraction of the cycle spent in that stage, if sampling is representative and cells progress comparably.
Quiz questions
Which sequence gives the five stages of mitosis in order?Answer: Prophase, prometaphase, metaphase, anaphase, telophase.
During prometaphase, what structure connects spindle microtubules to chromosomes?Answer: Kinetochores at the centromeric regions.
What allows sister chromatids to separate during anaphase?Answer: Degradation of cohesin proteins holding them together.
How does a plant cell typically form a new partition during cytokinesis?Answer: Golgi vesicles fuse into a cell plate that expands outward.
If 25% of cells are in a stage and the cycle lasts 24 hours, what is the estimated time in that stage?Answer: 6 hours.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.