Biology paper 1 (combined science AQA)

• Animal cells

  • Almost all cells differentiate at an early stage and then lose this ability
  • Most specialised cells can make more of the same cell by undergoing mitosis
  • Others such as red blood cells cannot divide and are replaced by adult stem cells
• Mitosis

  The process that involves a cell dividing to produce 2 identical cells
• Adult stem cells

  Retain their ability to undergo differentiation
• Cell division in mature animals

  • Mostly only happens to repair or replace damaged cells
  • Undergo little growth
• Plant cells

  • Many types retain the ability to differentiate throughout life
  • They only differentiate when they reach their final position in the plant
  • They can still re-differentiate when moved to another position