→ THE CELL CYCLE & MITOSIS
Intro to Cell Division
- All cells in an individual have identical DNA
● Mitosis
The process that produces two new nuclei with the same number and kinds of chromies
as the og nucleus.
- Ensures that each new cell inherits a complete set of the parent cells genetic info.
- Ensures the equal splitting of the DNA in cell division.
→ Examples of uses:
Unicellular Organisms (binary fission).
Zygote → Multicellular organism.
Old cells (skin) replaced with new cells.
Repair damaged tissue.
Cell Cycle
⭐︎Diagram in Notes
- Cell division occurs by a sequence of events called the cell cycle.
- Mitosis is just part (~10%) of the cell cycle.
- Cells must divide to maintain a high surface area:volume. Large cells can no longer
efficiently rely on diffusion for nutrient supply and waste removal.
● Interphase
- 90% of the cell life (when a cell does its job)
G1: cell grows
S: DNA duplication/replication
G2: more growth
● Mitosis & Cytokinesis
- 10% of cell life
→ Prophase
→ Metaphase
→ Anaphase ➤ Ensures equal distribution of DNA
→ Telophase
→ Cytokinesis : cell splits into 2 daughter cells / splits apart
, ⭐︎Interphase is in between everything
Prophase Prepare the chromies
Metaphase Meet in the middle
Anaphase Apart (pull apart)
Telophase The end.
Cytokinesis
● Interphase
3 Stages:
1. G1 (growth 1)
- DNA transcription-translation, growth, replication of organelles.
- Appearance of genetic material: chromatin, single stranded.
2. S (synthesis)
- DNA replication (new chromies)
- Appearance of genetic material: chromatin, double stranded
3. G2 (growth 2)
- DNA transcription-translation, structures associated with mitosis are
replicated (spindle proteins).
- Appearance of genetic material: chromatin, double stranded.
● Prophase
⭐︎Preparing
1. Chromatin condenses to form visible chromies.
2. Centrioles separate and move to the opposite poles of the cell.
3. Spindle fibres form.
4. Nuclear membranes and nuclei disappear.
Intro to Cell Division
- All cells in an individual have identical DNA
● Mitosis
The process that produces two new nuclei with the same number and kinds of chromies
as the og nucleus.
- Ensures that each new cell inherits a complete set of the parent cells genetic info.
- Ensures the equal splitting of the DNA in cell division.
→ Examples of uses:
Unicellular Organisms (binary fission).
Zygote → Multicellular organism.
Old cells (skin) replaced with new cells.
Repair damaged tissue.
Cell Cycle
⭐︎Diagram in Notes
- Cell division occurs by a sequence of events called the cell cycle.
- Mitosis is just part (~10%) of the cell cycle.
- Cells must divide to maintain a high surface area:volume. Large cells can no longer
efficiently rely on diffusion for nutrient supply and waste removal.
● Interphase
- 90% of the cell life (when a cell does its job)
G1: cell grows
S: DNA duplication/replication
G2: more growth
● Mitosis & Cytokinesis
- 10% of cell life
→ Prophase
→ Metaphase
→ Anaphase ➤ Ensures equal distribution of DNA
→ Telophase
→ Cytokinesis : cell splits into 2 daughter cells / splits apart
, ⭐︎Interphase is in between everything
Prophase Prepare the chromies
Metaphase Meet in the middle
Anaphase Apart (pull apart)
Telophase The end.
Cytokinesis
● Interphase
3 Stages:
1. G1 (growth 1)
- DNA transcription-translation, growth, replication of organelles.
- Appearance of genetic material: chromatin, single stranded.
2. S (synthesis)
- DNA replication (new chromies)
- Appearance of genetic material: chromatin, double stranded
3. G2 (growth 2)
- DNA transcription-translation, structures associated with mitosis are
replicated (spindle proteins).
- Appearance of genetic material: chromatin, double stranded.
● Prophase
⭐︎Preparing
1. Chromatin condenses to form visible chromies.
2. Centrioles separate and move to the opposite poles of the cell.
3. Spindle fibres form.
4. Nuclear membranes and nuclei disappear.
