mitosis phases

• Chromatin

  Loosely coiled threads of DNA
• DNA replicationduring interphase

  1. Chromosomes replicate

  2. Each chromosome now has a pair of chromatids, attached by a centromere
• Prophase

  • Replicated chromosomes become visible, they shorten and thicken
  • longest phase
  • Nucleolus disappears
  • Nuclear membrane disappears
  • Centromeres move to opposite poles
  • Spindle fibres start to form
• Metaphase

  • Replicated chromosomes line up at the equator in a single row
  • Spindle fibres attached to the centromeres
• Anaphase

  • very rapid phase
  • Centromeres split into two and the spindle fibres pull the centromeres to the opposite poles
  • The daughter chromosomes are pulled along behind the centromeres
• Telophase

  • Daughter chromosomes (unreplicated chromosomes) reach the opposite poles, and start to uncoil and lengthen to form chromatin network
  • Nuclear membrane reforms
  • Nucleolus reappears
  • Spindle fibres disintegrate
• Cytokinesis in animal cells

  1. Cell membrane constricts at the equator

  2. Two separate cells have now formed
• Cytokinesis in plant cells

  Cell plate made of pectin is formed at the equator
• Interphase

  The phase in which a cell spends most of its life time in
• Late interphase

  • When the cell needs to replicate
  • The cell starts to change
  • Organelles and centrioles start to replicate
• No centrioles in plant cell division
• Chromosomal material

  Loosely coiled threads called chromatin
• DNA replicationduring late interphase

  1. All chromosomes replicate

  2. Each chromosome will now have a pair of chromatids

  3. Chromatids attached by a centromere