Capillarity in the stem

To show the rising of sap through the woody vessels.

Water, cells and plants

capillarity; xylem; plant transport

What students learn

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 — 1680.06
Test tubes — 1473.60
2 sticks of celery with leaves

Chemicals and reagents

Water
Methyl blue dye — R:20/21/22

Safety notes

Questions for students

Observe what happens after different times. Try to give an explanation.

What to expect

<p>The water level drops in both test tubes.</p><p>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.</p>

Disposal

Dispose of the liquid into the waste container.

Run this experiment in your classroom

This experiment is part of the ATP Mobile Lab — a self-contained laboratory that turns an ordinary classroom into a working science lab, 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 Mobile Lab Talk to our team