Water conduction in celery xylem

A plastic storage container was filled with water the day before against the possibility of the water being off on lab day. The storage container permits cutting the celery underwater. This proved necessary after the lab failed two years ago when the celery was cut in open air.

Some of the lessons learned and countermeasures were outlined on the board.

The calculations were after 30 minutes.

Rulers were forgotten this term. The celery worked better than expected. All stalks.

The Erlenmeyer flasks were all filled to 100 ml. 100 ml proved sufficient.

Red dye was added drop by drop. An initial load of two drops was insufficient. Three more didn't make a lot of difference. More drops were added, perhaps ten to a dozen per flask.

The resulting dyed water was perhaps not as dark as last year. This made seeing the conduction hard to impossible. Yet the low dye amounts might explain the subsequent rapid rise of the dyed water in the celery. Food dye is not recommended for this lab as the dye molecules are reportedly quite large and could block the xylem. The lower levels of dye might explain the unexpected success in the leafless stalks. The leafless stalks showed no conduction last year.

Alex and Ronney worked with the inner stalks. These proved easier to see the red dye moving up in them, although it was still quite subtle. A cell phone light didn't help as much as hoped for. Perhaps other colors would be better.

The leafless celery was not expected to conduct, and the green stem prevented seeing what was happening in the xylem.

This was another celery not expected to conduct, but did so none-the-less.

Susan and Mirabella 

Harston with a leafed stem

Beverly, Trisden, Jenry-Thor, Amaryssa, Lensileen, Lyviane

Sweethy, Santriko, Ronney, Mitchy

Four or five xylem tubes have conducted dyed water

The shock was that conduction not only occurred in the leafless control stalks, but that the conduction happened in less than 30 minutes. This suggests the stalks should be pulled out early, perhaps very early, and then sliced down until the top of conduction is located. 

The above celery stalk is 23 centimeters.

The post-lab results, such as they are, along with a calculation that conducting water up the 115 foot tall Acacia tree would take 2.4 days based on the celery conduction data. The celery data is viewed as being too slow: the times are longer than the actual time for the dye to conduct.