cell cycle

• prokaryotes contain a single circular DNA chromosome in the cytoplasm
• Eukaryotes contain multiple chromosomes in the nucleus.
• DNA is six and a half feet long
• we have 2 forms of DNA which are super coiled DNA (chromosome) and loosely coiled DNA (chromatin)
• 1. we have a loosely coiled DNA (chromatin)
  2. The DNA then wraps around histone proteins to form nucleosomes(which are still in the chromatin form)
  3. then the nucleosomes condense until they form coils
  4. the coils condense even more to form supercoils
  5. which then form chromosomes
• 1 chromosome has 2 sister chromatid
• 1 chromosome has 4 telomere(ends of sister chromatid)
• centromere holds the 2 sister chromatids
• cell cycle is the stage of the cell's life. During the cell cycle, a cell grows prepares for division, and then divides to form two daughter cells
• importance of cell division:

  • renewal and replacement of dead/old cells
  • helps organisms to grow
  • healing injuries
  • reproduction (when sex cells divide)