Tag Archives: Mitosis


Reasons for Cell Division

  • Cell division is required for:
    • a) growth
    • b) repair & replacement of damaged parts
    • c) reproduction of the species

In Cell Division Copies of the DNA Must Be Sent to Both New Cells

  • Since the instructions for making cell parts are encoded in the DNA, each new cell must get a complete set of the DNA molecules
  • This requires that the DNA be copied (replicated, duplicated) before cell division

Genetic Blueprints for Cells Are Organized Into Chromosomes

  • The plans for making cells are coded in DNA

Cells: Structure & Function

All Living Organisms are Made Up of Units Called Cells

  • Cell theory:
    • All living creatures are made from 1 or more cells
    • All cells are produced from previously existing cells (no spontaneous generation)
  • All cells appear to be descended from the first cell which existed about 4 billion years ago
  • For a species to exist its reproductive cells must be potentially immortal (no aging)
  • Our bodies start from a single cell and contain about 100,000,000,000,000 (10^13) cells at maturity

There Are 2 Basic Types of Cells: Prokaryotic and Eukaryotic