Biology

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

Glassware

Broken glass is sharp

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