What is the cell cycle?
The sequence of events where a cell duplicates its genome, synthesizes constituents, and divides.
How long does a typical human cell take to complete its cell cycle?
Approximately 24 hours.
How long does yeast take to complete its cell cycle?
About 90 minutes.
What are the two main phases of the cell cycle?
Interphase and M phase.
What happens during interphase in the cell cycle?
The cell prepares for division.
What occurs during the M phase of the cell cycle?
Mitosis and usually cytokinesis occur.
Which phases make up interphase in the cell cycle?
G1, S, and G2 phases make up interphase.
What happens to DNA content during the S phase?
DNA content doubles from 2C to 4C during S phase.
Does chromosome number change during the S phase?
Chromosome number remains unchanged during S phase.
What is the quiescent stage (G0) in the cell cycle?
G0 is an inactive stage where cells do not proliferate but remain metabolically active.
Which stages does mitosis proceed through in order?
Prophase, metaphase, anaphase, and telophase.
What happens to chromosomes during prophase of mitosis?
Chromosomes condense.
What occurs during metaphase in mitosis?
Chromosomes align at the cell equator.
What is the key event in anaphase of mitosis?
Sister chromatids separate.
What happens during telophase in mitosis?
Daughter nuclei reform.
How do spindle fibres interact with chromosomes at metaphase?
They attach to kinetochores with sister chromatids connected to opposite poles.
How does animal cytokinesis occur?
By an inward-cleaving plasma-membrane furrow.
How does plant cytokinesis occur?
By a cell plate that forms centrally and grows outward to lateral walls.
What forms if karyokinesis is not followed by cytokinesis?
A multinucleate syncytium.
Why is mitosis called equational division?
Because the chromosome number is conserved in daughter cells.
What type of daughter cells does mitosis produce?
Genetically identical daughter cells.
Which processes does mitosis support in multicellular organisms?
Growth, cell repair, and replacement of epidermal, gut-lining, and blood cells.
How does mitosis contribute to continuous plant growth?
By supporting growth in apical and lateral meristems.
What is meiosis?
A specialised division reducing diploid cells to haploid for sexual reproduction.
How many nuclear divisions occur in meiosis?
Two successive nuclear divisions occur in meiosis.
How many DNA replication cycles precede meiosis?
Only one DNA replication cycle precedes meiosis.
Which stages does prophase I include?
Leptotene, zygotene, pachytene, diplotene, and diakinesis.
What key events happen during prophase I?
Chromosomes condense, homologues synapse, crossing over occurs, chiasmata appear, and spindle forms.
What is crossing over?
Enzyme-mediated exchange of genetic material between non-sister chromatids during pachytene.
When does crossing over occur during meiosis?
During the pachytene stage of prophase I.
What does crossing over produce?
Genetic recombination.
What separates during anaphase I of meiosis?
Homologous chromosomes separate.
What remains joined during anaphase I of meiosis?
Sister chromatids remain joined at their centromeres.
What separates during anaphase II of meiosis?
Sister chromatids separate after centromeres split.
What marks the end of meiosis?
Telophase II and cytokinesis mark the end of meiosis.
How many daughter cells result from meiosis?
Four haploid daughter cells are produced.
What is interkinesis in meiosis?
A short stage between meiosis I and II when DNA does not replicate.
How does meiosis maintain species-specific chromosome number?
By producing haploid gametes through chromosome reduction.
What restores the diploid phase after meiosis?
Fertilisation restores the diploid phase.
How does meiosis affect genetic variability between generations?
Meiosis increases genetic variability between generations.
Why is genetic variation from meiosis important?
It is important for evolution.
Test your knowledge with 18 questions on Cell Cycle and Cell Division.
1. Which sequence best describes the cell cycle?
2. Which statement correctly distinguishes interphase from M phase?
Review the complete course in the study sheet for Cell Cycle and Cell Division.
See study sheet →Import your course and AI generates flashcards in 30 seconds.
Flashcard generator