Chapter 11 ContRol of Gene ExpressioN
Cell Cycle
- The cell cycle is a series of events from the time a cell forms until its cytoplasm
Interphase
- This stage is the internal between when miotic divion and when a cell grows, and it spends most of its life in this stage
- This is when the cell replicates its DNA and doubles the number of cytoplasmic components
- There are 3 stages G1, S, and G2
Prophase
- This is the first stage of mitosis, and the chromosomes are condensed
- The nuclear envelope breaks up
- Spindles made of microtubules form at each end of the cell
Metaphase
- The chromosomes align in the middle of the cell
- They are pushed and pulled by the microtubules to align in between the spindles
Anaphase
- The microtubules the sister and the parent chromosomes to opposite sides
- This makes separate chromosomes
Telophase
- This is when the two chromosomes reach either end of the cell
- The two bunches are exactly the same and have the same DNA
- Then, a nuclear envelope starts to form around each cluster
- This is the end of mitosis
Telomeres
- These are noncoding DNA sequences at the end of eukaryotic chromosomes
- They are junk sequences, but are essential to living a long life
- They provide a buffer between the essential DNA, because each time a cell divides, a chromosomes lose about 100 nucleotides
