22. Investigation into the role of nitrogen and magnesium in plant growth

  • 00:35 Why do you set up 5 test tubes of each solution?
  • 00:53 Why should you wrap foil round the tubes?
  • 01:02 Why must all seedlings be placed in the same light and temperature conditions?
  • 01:10 Why is dry mass measured?
  • 01:14 What differences do you observe between the seedlings?
  • 01:16 What explanations can you give for any observed and measured differences between the seedlings?
  • sach’s complete water culture solution

  • sach’s water culture solution lacking nitrate ions

  • sach’s water culture solution lacking magnesium ions

  • test tubes (1 per culture solution)

  • cotton wool

  • aluminium foil

  • dropping pipette

  • germinated barley seedlings

Hazard Risk Control measure


Broken glass is sharp

Care when using so as not to break. If breakage occurs, sweep up and dispose of broken glass carefully.