L7-9 quiz

• doubling time of 24 hours, 2.5 million cells were added to a tissue, how many cells after 96 hours?

  40 million (4 doublings)
• less cells than expected from the doubling time of a cell because:

  • cells have entered senescence
  • growth media doesn't have the relevant growth factors for cell survival and growth
  • contact inhibition
• if a cell has transformed then there will be

  more cells than predicted from the doubling time
• contact inhibition is:


  cells next to each other attempt to alter their locomotion to avoid future collisions, when unable to avoid collisions, the cells culture stops in cell0density dependent manner)
• embryonic stem cells are described as

  pluripotent
• plant cells totipotency refers to the capacity of plant cells to

  regenerate a mature organism
• characteristic of transformed cell line:

  • increased motility
  • immortal
  • anchorage independent
  • no contact inhibition
  • less differentiated (as lose specialised characteristics)
• components required to grow cells in culture:

  • vitamins
  • nutrient source
  • culture media
  • growth factors
• Agrobacterium Ti plasmid:

  • T-DNA is the only part of the Ti plasmid that is transferred to the host plant
  • only the left and right border sequences of the T-DNA and its repeat sequences are required for its integration into the plant genome
  • Vir region is needed for gene transfer process
• floral dipping is an applicable method for generating transgenic plants
• somaclonal variation is a phenomenon associated with plant tissue culture
• term for cells which make monoclonal antibodies and are fusion of antibody-producing spleen cells and immortal myeloma cells 


  hybridomas