mitosis

• mitotic cell division

  form of asexual reproduction. it is cellular reproduction involving a single parent cell resulting in genetically identical daughter cells
• cells divide for..

  • reproduction
  • growth
  • repair and maintenance (replace dead or damaged cells)
• interphase is 90% of the cell cycle
• interphase


  cell grows and performs normal functions. longest part of the cell cycle.
• interphase duration varies due to different cell types
• three phases of interphase

  • Gap1 (G1)
  • S (synthesis)
  • Gap2 (G2)
• Gap1 (interphase)

  rapid growth following division
• Synthesis (interphase)

  DNA replication occurs, DNA copied
• Gap2 (interphase)

  replication of organelles and prep for cell division
• Mitosis

  separation of identical DNA copies
• Phases of mitosis:

  1. prophase
  2. metaphase
  3. anaphase
  4. telophase
• label the chromosome

  A) chromatid

  B) chromatid

  C) double-stranded

  
• prophase

  • nuclear membrane and nucleolus disappear 
  • spindle fibres form between each end of cell
  • in animal cells, centrioles move to cell poles, aster rays form around centrioles
  • chromatin condenses to form chromatids joined together at centromeres to form chromosomes
• at the beginning of prophase, the DNA is in the form of long-thin chromatin

  by the end of prophase, the DNA is in the form  of short-thick chromosomes
• label the diagram

  A) spindle fibres

  B) aster rays

  C) centrioles

  
• metaphase


  spindle fibres move chromosomes to equator of the cell (middle)
• anaphase


  spindle fibres separate chromatids into single-stranded chromosomes and pulls them towards the poles
• when double-stranded chromosomes separate, they form two single-stranded chromosomes
• At the beginning of telophase, the DNA is in the form of short-thick single chromosomes.

  By the end, the DNA has uncoiled and is in the form of long-thin chromatin
• during telophase, the nuclear membrane and nucleolus reappear
• cytokinesis


  division of cytoplasm and organelles. organelles in the cytoplasm divide and are distributed among the new daughter cells
• label the diagram

  A) cleavage furrow

  
• label the diagram

  A) cell plate