Mitosis Flashcards
(26 cards)
What is the cell cycle?
A series of events that occur in a cell as it divides.
What are the phases of the cell cycle?
- Interphase
- Mitotic phase
What occurs during interphase?
Cell growth, DNA replication, and mitosis preparation.
What is the mitotic phase?
The shortest part of the cell cycle where mitosis occurs.
What are the stages of mitosis?
- Prophase
- Prometaphase
- Metaphase
- Anaphase
- Telophase
What characterizes the G1 (first gap) phase?
Cell becomes larger in size.
What happens during prophase?
- Chromosomes condense
- Homologous pairs appear
- Mitotic spindle forms
- Nucleolus disappears
What happens in prometaphase?
- Nuclear envelope breaks down
- Chromosomes become visible as duplicated chromosomes
- Kinetochores form
What is the significance of the S (synthesis) phase?
Chromosomes and centrosomes are duplicated.
What occurs during the G2 (second gap) phase?
- Cells continue growing
- Protein synthesis occurs
- Organelles are reorganized for mitosis
What is the role of the mitotic spindle?
To separate chromosomes during cell division.
What happens during telophase?
- Nucleolus and nuclear envelope reappear
- Chromosomes become less condensed
What is cytokinesis?
The process that divides the cytoplasm of a parental cell into two daughter cells.
What is binary fission?
A type of cell division in bacteria where a single chromosome replicates.
What are the three checkpoints in the cell cycle?
- G1 Restriction checkpoint
- G2 checkpoint
- Metaphase checkpoint
What does the G1 Restriction checkpoint assess?
Whether the cell can continue in the cell cycle.
What are regulatory proteins in the cell cycle?
- Protein kinases
- Cyclins
What is the function of cyclins?
To activate cyclin-dependent kinases (CDKs) for cell cycle progression.
What happens to cyclin during anaphase?
Cyclin degrades, indicating that mitosis is completed.
Define growth factors.
Proteins secreted by certain cells that stimulate mitosis.
What is anchorage dependence?
The requirement for cells to attach to a surface for survival and proliferation.
What is density-dependent inhibition?
Crowded cells stop dividing.
True or False: Cancer cells adhere to anchorage dependence.
False
What do cancer cells require for growth?
They can grow without growth factors or bypass growth factor signaling.
