Limp Celery

Celery pieces are soaked in salt water and fresh water to show how water moves in or out of plant cells by osmosis, changing texture from rigid to limp.

1. Prepare two containers: one with fresh water and one with salt water (stir to dissolve thoroughly).
2. Note initial texture of the celery - gently bend it to see that it is rigid..
3. Place a celery pieces into each container so they it is completely covered.
4. Leave for at least 30 minutes (longer or overnight gives a stronger effect).
5. Remove from the salt water. Briefly rinse in fresh water to remove surface salt. Compare flexibility to the original piece.
6. Repeat with the sample from the fresh water (no rinse needed). Compare flexibility and taste to the original piece.

Celery Plant Demonstration - CYBER. ORG:

📄 With both celery and carrots, going into great detail: https://sealevel.jpl.nasa.gov/files/archive/activities/ts3siac1.pdf

• Try with other vegetables such as carrots.
• Once finished, move the salt‑soaked piece into a new container of fresh water for at least 30 minutes, then reassess texture.
• Use ocean‑like brine (about 35 g salt per liter) versus a milder brine to compare the strength of the effect.
• Start with intentionally limp celery or carrots and observe how fresh water can restore crispness.
• Extend the investigation over 1–3 days and record changes at several time points.
• Compare different cut sizes (thin sticks vs. thicker chunks) to see how surface area affects the rate.

• Experiments done in the lab should never be tasted. This one could be done in a kitchen setting and tasted.

• Why do many ocean organisms maintain high internal salt levels? To reduce water loss to the surrounding seawater and avoid dehydration.
• If a freshwater plant or fish is placed in seawater, what osmotic problem do they face? Water tends to leave their bodies, causing dehydration unless they have adaptations to prevent it.