Cell Cycle
Events that occur from when a cell is made until it has
divided into 2 new cells.
Mitosis
Nucleus splits
Interphase
Growth, synthesis, DNA
replication
Cytokinesis
Cytoplasm splits into 2
cells
Chromatids
REMIND ABOUT TERM CHROMATID =
when chromosomes replicated and joined
by centromere
Mitosis video
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Mitosis
4 Phases:Prophase
Metaphase
Anaphase
Telophase
Prophase
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Chromatids condense (shorter and thicker)
Nuclear membrane disintegrates
Centrioles separate
Spindle starts to form from centrioles
Metaphase
• Spindle has been formed
• Chromatids attach to spindle by
centromere
• Chromatid pairs line up, in single file,
along equator of cell
Anaphase
• Centromeres split into 2
• Spindle fibres shorted to pull chromosomes to
poles
• Chromosomes pulled towards pole, centromere
first
Telophase
• Spindle disintegrates
• Nuclear membrane reforms (cell has 2
nuclei)
Key Words
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•
•
•
•
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Chromatid
Centromere
Spinde fibres
Equator
Nuclear envelope
poles
- prophase
- metaphase
- anaphase
- telophase
Mitosis
Stage
Chromosomes
Other events
Prophase
•Consist of 2 chromatids joined by
centromere
•Condense (shorter and fatter)
•Become visible
•Nuclear envelope disintergrates
•Centrioles at poles
•Spindle starts to form
Metaphase
•Still consist of 2 chromatids joined
by centromere
•Centromeres attach chromatid
pairs to spindle fibres
•Chromatid pairs line up along the
equator of the cell
•Spindle formed
Anaphase
•Centromere holding chromatids
splits to separate the chromatids
(when split = chromosomes)
•Chromosomes pulled to opposite
poles by spindle fibres contracting
•Pulled centromere first
•Spindle fibres contract
Telophase
•Become long and thin = not visible
•Nuclear envelop forms around
chromosomes at each end of cell
•Spindle disintergrates
Interphase
Prophase
1
Metaphase
Anaphase
Telophase
Interphase
2
Prophase
Metaphase
Anaphase
Telophase
Interphase
Prophase
3
Metaphase
Anaphase
Telophase
Interphase
Prophase
4
Metaphase
Anaphase
Telophase
Interphase
5
Prophase
Metaphase
Anaphase
Telophase
Interphase
Prophase
6
Metaphase
Anaphase
Telophase
Interphase
Prophase
7
Metaphase
Anaphase
Telophase
Interphase
Prophase
1
Metaphase
Anaphase
Telophase
Interphase
2
Prophase
Metaphase
Anaphase
Telophase
Interphase
Prophase
3
Metaphase
Anaphase
Telophase
Interphase
Prophase
4
Metaphase
Anaphase
Telophase
Interphase
5
Prophase
Metaphase
Anaphase
Telophase
Interphase
Prophase
6
Metaphase
Anaphase
Telophase
Interphase
Prophase
7
Metaphase
Anaphase
Telophase
Cell division –
label as many things as possible
Task
Write a poem following the rules below.
Your first word is “MITOSIS”
One word for the idea
e.g. school
Two words to explain the meaning of the idea
e.g. learn things
Three words to describe what the idea does
e.g. educate and train
Four words to explain what the idea means to you
e.g. interesting and fun activities
One final word for the idea
e.g. education
Feature
Mitosis
Meiosis
Number of divisions
1
2
Number of daughter cells
2
4
Diploid or haploid cells
produced?
How do chromatid pairs line
up for first division
Diploid
Haploid
Single file
In
homologous
pairs (as
bivalents
Chromosome
pairs
What is split in first division
Chromatid
pairs
Variation in daughter cells?
No (unless
mutation)
Yes
Feature
Number of divisions
Number of daughter cells
Diploid or haploid cells
produced?
How do chromatid pairs line
up for first division
What is split in first division
Variation in daughter cells?
Mitosis
Meiosis