Binary fission, budding and Mitosis Flashcards
Why do cells divide?
- To produce gametes
- To repair damaged tissue
- For embryonic development
- For growth
- Cancerous cells
What four events must happen before cell division?
DNA replication, growth, chromosome segregation and organelle duplication.
Why is binary fission beneficial?
Its very simple and fast.
How is binary fission induced?
By signals such as environmental figures or nutrient concentration.
What is the most common mechanism of division in prokaryotes?
Binary fission
How do DNA replication and division occur in binary fission?
Simultaneously
What controls cytoplasmic separation in binary fission?
Fitz protein
How big are the daughter cells of budding relative to the parent cell?
Smaller
What effect does the daughter cell of budding have on the parent cell?
It leaves a scar on the parent cell where it grew.
How does the new organism develop in budding?
A new organism develops from the outgrowth of the parent cell.
What is a bud?
A small bulb like projection from the parent cell.
When does the daughter cell detach from the parent in budding?
When it has fully matured.
How does cell separation occur in budding?
A chitin ring is formed at the cell wall by CS111. This forms a primary septum by CS11. CS111 then forms a secondary septum.
How are chromosomes arranged in G1?
They are single, replicated molecules with associated proteins. (chromatin)
What happens during G1?
The cell performs normal function and grows.
Centrosomes undergo replication.
What happens in S phase?
The cell pauses normal function and DNA replicates. Each chromosome joins with another and they become two sister chromatids.
What happens in G2?
The cell adds volume to the cytoplasm and organelles are duplicated. In animals mitochondria are duplicated and in plats mitochondria and chloroplast are replicated.
Where is the minus end of the microtubule?
Near the centrosome.
Where is the plus end of the microtubule?
Near the chromosome.
What is the function of microtubules?
To maintain cell shape and integrity.
What are microtubules made of?
Tubulin
What happens in prophase?
Chromatin condenses into chromosomes and is now visible. The centrosomes move apart and form the mitotic spindle. The nuclear envelope breaks down and kinetochore microtubules attach at the centromere of the chromosome.
What happens in metaphase?
The chromosomes align at the metaphase plate. The metaphase checkpoint ensure the kinetochores are correctly attached to the mitotic spindle.
What happens in anaphase?
Separase is hydrolysed by protease and causes chromatid separation by removal of cohesion.
Chromatids are pulled to opposite poles by microtubules and the cell elongates.
