C Flashcards
What is the purpose of mitosis?
To produce new cells via duplication of existing cells
Important in development, growth, and healing.
How many phases are there in the eukaryotic cell cycle?
Four phases
The phases are G1, S, G2, and M.
What occurs during the G1 phase of the cell cycle?
Cell growth and doubling of mass of proteins and organelles.
What is the S phase responsible for?
DNA synthesis and duplication of chromosomes.
What happens during the G2 phase?
Preparation for mitosis and monitoring of internal and external conditions.
What does the M phase include?
Nuclear division (mitosis) and cytoplasmic division (cytokinesis).
What triggers the major events of the cell cycle?
Cell Cycle Control System.
True or False: Cancer cells can ignore the cell cycle control system.
True.
What occurs during prophase of mitosis?
Replicated chromosomes condense and centrosomes replicate and move apart.
What is the metaphase plate?
The alignment of chromosomes in the middle of the spindle during metaphase.
What happens during anaphase of mitosis?
Sister chromatids are pulled towards opposite poles.
What is cytokinesis?
Division of the cytoplasm to form two daughter cells.
What is meiosis?
A specialized form of nuclear division involved in sexual reproduction.
What type of cells does meiosis produce?
Haploid cells (gametes).
Fill in the blank: Meiosis involves _______ round(s) of DNA replication followed by _______ round(s) of cell division.
One; two.
What is the difference between meiosis I and meiosis II?
Meiosis I separates homologous chromosomes; meiosis II separates sister chromatids.
What is a bivalent in meiosis?
A four-chromatid structure formed by homologous chromosomes pairing.
What occurs during crossing-over?
Exchange of DNA segments between homologous chromosomes.
What mechanisms generate genetic variation during meiosis?
- Independent assortment of chromosomes
- Crossing-over during prophase I.
True or False: No DNA replication occurs between meiosis I and meiosis II.
True.
What is the result of meiosis?
Four haploid cells with either maternal or paternal copies of each chromosome.
How many different haploid gametes can be produced for an organism with n chromosomes?
2^n different haploid gametes.
