what are the Series of events that take place so that it can divide into 2 daughter cells(simplify mitosis)
○ Cell growth
○ DNA replication
○ Distribution of duplicated chromos to daughter cells
○ Cell division
what is B period in bacterial cell division
cell growth
what is c period in bacterial cell division
Chromosome replication
where on the
chromosome does replication begin in the C period
at a single site called the Origin of Replication (ori)
2 oris go along either side of the circular DNA until they meet and then divide
what is the d period in bacterial cell division
Binary Fission (cell division)
whats the difference between prok and euk cell division
Pro:
- 1 chromosome
- Has nucleoid
- Division = binary fission
Euk:
- Many chromos
- Has nucleus
- Division = Mitosis
what r the 3 phases of Interphase
G1 - Growth
S - Replicates material
G2 - Prepares for cell division
what are all the phases of mitosis
Prophase
Prometaphase
Metaphase
Anaphase
Telophase
Cytokinesis
what happens in prophase
- Chromos compact into rodlike structure
- Centrosome migrates to form spindle poles and forms spindle in cytoplasm
what happens in prometaphase
- Nuclear envelope disappears
- Spindle enters former nuclear area
- Kinetochore protein assembles at centromere
- Microtubules form spindles that attach to Kinetochores on the chromos
what happens in Metaphase
- Spindle is fully formed
- Chromos align at center (metaphase plate)
- Moved by spindle microtubules
What happens in anaphase
- Spindles separate chromos into sister chromatids
- Chromo segregation complete
What happens in telophase
- Spindles disassemble
- Chromos decondense
- New nuclear envelope forms around chromos
What happens in animal cytokinesis
- divides cell
- Microfilaments slide together and tighten band, gradually separates cytoplasm’s
what happens in plant cytokinesis
- Cell wall material is deposited by vesicles to centre / midpoint
- Deposition continues until new wall separates daughter cells
Definition of chromosome
Nuclear units of genetic information that are duplicates. Segregated and distributed by mitotic cells division
What is a Haploid
a creature with 1set of chromos
what is a diploid
creature with 2 sets of chromos
What does the nucelosome consist of (histone complex)
- Histon proteins 1-4
- DNA coiled up around these proteins
How does spindle formation occur in Plant cells
- from microtubules (multiple organizing centres)
- Assemble in all directions surrounding nucleus
Hoe does spindle formation occur in animal cells
- Centrosome divides
- Microtubules from centrosomes form early spindle
what r 2 types of Microtubules
Kinetochores
Non-Kinetochores
what does a Kinetochore Microtubule do
segregate daughter chromos
What do Non-Kinetochore microtubules do
- Extend cell
- Bring centrosome further apart
- Overlap eachother
