Eukaryotic Cell Division
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Eukaryotic Cell Division Occurs by Mitosis Q: What type of cell does mitosis occur in? A: Somatic cells or body cells (2n)
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Eukaryotic Cell Division. Occurs by Mitosis Q: What type of cell does mitosis occur in? A: Somatic cells or body cells (2n). The Cell Cycle. Cell cycle = period from the beginning of one cell division to the beginning of the next. Why is cell division important?. The Cell Cycle. - PowerPoint PPT Presentation
Transcript of Eukaryotic Cell Division
Eukaryotic Cell DivisionOccurs by Mitosis
Q: What type of cell does mitosis occur in?
A: Somatic cells or body cells (2n)
The Cell CycleCell cycle = period from the beginning of one
cell division to the beginning of the next.
Why is cell division important?
The Cell CycleThree important functions of cell division for
organisms:
1.Growth – grow from single cell to multi-cellular organism
2.Maintenance – replacement of worn out cells (e.g. Blood cells)
3.Repair – cell division regenerates damaged tissues
Cells divide for an organism to surviveResult of cell division
= two new cells (daughter cells) that are identical to the original cell (parent cell)
Why are the daughter cells identical?• They contain an exact copy of the parent cell’s
hereditary material – DNA (deoxyribonucleic acid)– DNA store the instructions that determine the details
of the organism’s life (characteristics, functions, life span)
Cells divide for an organism to surviveDNA – is store in the nucleus of eukaryotic cells
- it forms thread-like coils called chromatin, which we usually can’t see
- when a cell divides, the chromatin condenses and forms chromosomes, which we can see
Why is cell Replication in Eukaryotes more complicated?
• complicated because:
– DNA is divide among several linear chromosomes
– DNA is contained within a nucleus
– cell has several membrane bound organelles
Source:http://commons.wikimedia.org/wiki/File:Kasvisolu.png
Three Stages of the Cell Cycle• Stage 1 – Interphase
– Growth and preparation of cell for division – DNA replication occurs in this stage– Consists of G1, S, G2 phases
• Stage 2 – Mitosis– Division of the nucleus– Consists of 4 phases
• Stage 3 – Cytokinesis– Division of the cytoplasm and organelles
Growth Stage
Division Stage
The Eukaryotic Cell Cycle
*Separation of centrosomes
Spindle fibres from opposite poles attach to the centromere of each chromosome
* Spindle fibres shorten
• Division of cytoplasm (cell pinches in two)
• creates a cleavage furrow
• Cleavage furrow
Chromosome Structure
