Cell turgor
To demonstrate how the water content in plant fibres is responsible for herbaceous plants standing up.
The science behind this experiment
Osmosis affects the consistency of plant fibres by swelling or shrinking cells. Tissues rich in water are turgid, while tissues that have lost water appear flaccid. This experiment demonstrates how a flower can stand up, and here too the water content in the cells is decisive.
Equipment used
- Petri dishes — PLA-001
- Scalpel — PLA-026
- Tweezers — PLA-025
- Dandelion (Taraxacum officinale)
Chemicals and reagents
- Sodium chloride solution 10%
- Distilled water
Questions for students
- What happens to the dandelion, and on which side of the curl is the epidermis?
- What happens on swapping the solutions?
- Explain the process that occurs in the cells of the stem. Do you think this process is responsible for the flower standing up?
What to expect
The curls change side obtaining finally the same situation as above. In distilled water tissues absorb water increasing their turgor and hence causing a mechanical stress on the epidermis which curls the strips. Swelling increases the dimensions of the tissues whilst epidermis dimensions remain unchanged. Also in saline solution strips curl due to mechanical stress but in this case the effects are inverted, as a matter of fact.
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