The Cell Cycle Flashcards
Why do cells reproduce?
- Growth and development of multicellular organisms
- Tissue repair/renewal (cells don’t last forever)
What are the three stages of Interphase?
G1, S, G2
What occurs during the G1 interphase stage?
Normal functions of the cell & growth.
What occurs during the S interphase stage?
The cell’s DNA is replicated, and centrosomes are duplicated.
What occurs during the G2 Interphase stage?
The cell grows again, and it checks the duplicated chromosomes for errors.
What are the 4 stages of mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
What occurs during the prophase of mitosis?
- Condensation (i.e. thickening) of the chromosomes.
- Kinetochores appear at the centromeres
- Mitotic spindle microtubules (from the cytoskeleton) attach to kinetochores
What happens during the Metaphase of mitosis?
- The nucleus is disassembled
- The chromatids are aligned in the middle (centre) of the cell.
What occurs during the Anaphase of mitosis?
- Chromatids are pulled to either side of the cell via spindles
What occurs during the Telophase of mitosis?
- Spindle is dismantled
- 2x new nuclei form
What occurs during cytokinesis?
- The splitting of the cell into two identical daughter cells
What are the 3 main stages of a cell life cycle?
- Interphase
- Mitosis
- Cytokinesis
How does an animal cell complete cytokinesis?
The mother cell is “pinched” in two at a cleavage furrow.
How does a plant cell complete cytokinesis?
- Vesicles fuse forming the cell plate
- The cell plate grows outward until its membrane fuses with the cell membrane, separating the 2 daughter cells
What are key features of mitosis for yeast (fungi)?
- During metaphase, one part of the cell membrane is branched out
- During anaphase, one part of the chromosome is dragged to the extra bud
- During cytokinesis, the extra bud’s membrane splits from the mother cell
When do mitochondria divide?
During G1 and G2 of interphase
How do mitochondria divide?
- During interphase, they divide via fission (so there are double the amount)
- They move so that there is an equal amount of both side of the cell prior to cytokinesis
How do prokaryote cells reproduce?
Via binary fission
What is the process of binary fission?
- DNA moves to either end of the cell
- The cell gets bigger
- A new membrane is fomed
