Water transportation in plants

Lesson plan

Links to National Curriculum

KS2 Science (year 3)
Scottish first level Science (Planet Earth)
Northern Ireland Interdependence

  • Estimated time: 30 minutes
  • Location: Indoors
  • School term: All year round
  • Key stage(s): KS1, KS2
  • Subject(s): Science

Learning objectives

  • Look at how water is transported within plants
  • Discover the function of different parts of a plant
  • Choose a type of scientific enquiry to use
  • Collect data from own observations

Key vocabulary

  • flower
  • stem
  • stalk
  • leaves
  • roots
  • transportation
  • vessels
  • xylem
  • evaporation

Introduction

Plants need water to grow.

What happens if we don't give our plants water? Observe potted plants and cut plants, give water to some, but not others. Record the results during a week.

Starter

Using the paper flower template, cut out a flower per pupil and fold the petals in towards the centre. Place the folded paper flower into a shallow saucer of water. Observe what happens. The flower should open as water moves through the fibres of the paper (capillary action).

Another good starter for looking at capillary action is the 'Walking water' activity.

Main activity

  1. Cut the stem of the carnation between 5-10cms from the bottom of the flower. Place the carnation in a clear container of coloured water (use water-based food colouring). Observe what happens over a period of 10-30 minutes - you should see the white petals slowly change colour. You could take a series of photographs, to track the changes of colour in the flower petals for pupils to refer to.         
  2. Try the same activity with leafy celery stalks.
  3. Using the cut leafy stems of the celery and recycled small water bottles, can learners devise an experiment to measure how much water is taken up by the stem, in an agreed time period? What method will learners choose to conduct this scientific enquiry? What success indicators will they be looking for? How will they measure and record their results? 

Plenary

Cut horizontally through a celery stem and observe the water transportation vessels called xylem. Use a magnifier to look closer.

Essential background information

The movement of water in plants is driven by a process called transpiration. This is where water evaporating from the leaves of a plant causes the plant to draw up more water from the roots. Water moves up the stem by capillary action - this is where water molecules seemingly 'stick' together.

To demonstratethis to your pupils, show them this short video from BBC Teach.

Resources

  • Stems of white carnation flowers, celery stalks (with leaves), cut leafy stems
  • Water based food colouring
  • Clear plastic container, bottle or glass
  • Paper flowers (Capillary Flowers)
  • Camera

Differentiation

Identify the factors that have an effect on plants taking up water.

Think about:
Temperature and location, amount of leaves

Assessment questions

  • Can you name the functions of plant parts?
  • Can you match parts of a plant with their functions?
  • Do some parts have more than one function?