Capillarity in the stem
A coloured solution rises through the woody vessels of a stem, showing how sap travels from the roots to the leaves in plants such as celery.
The science behind this experiment
The rising of sap through the stem, from the roots to the leaves, varies between species. In some plants such as celery this process occurs very quickly. In this experiment a coloured solution is seen rising through the woody vessels.
Equipment used
- Test tube rack — PLA-012
- Test tubes — PLA-007
- 2 sticks of celery with leaves
Chemicals and reagents
- Water
- Methyl blue dye — R:20/21/22
Questions for students
- Observe what happens after different times. Try to give an explanation.
What to expect
The water level drops in both test tubes. At the same time the celery stick, in the test tube containing the methyl blue dye, shows a blue colouration along the stem. As time goes by the coloration rises up reaching the leaves, demonstrating how the lymph is taken from roots to the leaves through the woody vases.
Disposal
Dispose of the liquid into the waste container.
Run this experiment in your classroom
This experiment is part of ATP Volta — a self-contained mobile science lab that turns an ordinary classroom into a working STEM laboratory, with over 200 experiments in physics, chemistry, biology, robotics and engineering. Gali, the AI tutor built into ATP Connect, guides students through each step and answers their questions at the bench.
See the ATP Volta mobile science labTalk to our team