Term
| What are the mitosis-division of the nucleus of a eukaryotic cell? |
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Definition
- G1 (G0)--the cell is not dividing (the longest phase)
- S --when DNA replicates
- G2 -- the gap between S and M
- M --(4 phases) (the shortest phase) |
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Term
| What are the 2 major checkpoints? |
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Definition
1. G1 checkpoint
- makes sure the environment is favorable & has DNA intact
2. G2 checkpoint
- Makes sure the DNA replicates & finish |
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Term
| What are the Phases of mitosis? |
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Definition
Prophase: nuclear envelope disappears, initiation of mitotic spindle
Metaphase: chromosomes arrange in equatorial plane, spindle complete
Anaphase: splitting of chromosomes & migration to poles
Telephase: nuclear envelope reappears & chromosomes de-condense |
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Term
| What are the 2 required proteins? |
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Definition
Cohesin - ACTIVATED DURING S PHASE AND RESPONSIBLE FOR GLUING THE 2 SISTER CHROMATINS TOGETHER
Condensins - ACTIVATED DURING M PHASE & MEDIATES INTRAMOLECULAR CROSS-LINKING TO COIL DNA IN THE PROCESS OF CHROMOSOME CONDENSATION |
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Term
| Whats the role of Microtubles? |
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Definition
Microtubles form the mitotic spindle
-help connect kinetochores
-During anaphase
- shortening of the kinetochores microtubles causes the movement of daughter chromosomes to poles
- Dependent on the motor protein dynein |
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Term
| What is the name of the anti-miotic drug? |
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Definition
-TAXOL
-it binds tightly to Microtubles & stabilizes them
-cells arrested @ mitosis w/ taxol will undergo apoptosis
- it will kill every dividing cell/cancer |
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Term
| What is the role of actin filaments (microfilaments) during mitosis? |
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Definition
- forms the contractile ring (actin & myosin) during cytokinesis |
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Term
| What is the role of intermediate filaments in mitosis? |
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Definition
- links chromatin to nuclear envelpe
- Phosphorylation of lamins triggers disassembly of nuclear lamina, which causes nuclear envelop to disassembly |
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Term
| What happens to organelles during Mitosis? |
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Definition
-ER -- vesiculates when nuclear envelope breaks down during prophase & reforms during telophase
-Golgi -- is similar to ER
-Mitochondria, lysosome, peroxisomes -- nothing
**everything stops except for components involved in cell division |
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