Food Dye Affecting Plant Drinking

[deleted-319815]

I'm doing a lab experiment for my biology class and need some background information about how dye (food coloring) affects the amount of water that flowers drink. If you could get me this information along with a website(s) to use as sources that would be great..... The more websites the better.

[SciB]

Hi,

Is this the project you are doing: https://www.sciencebuddies.org/science- ... p033.shtml
?

If so then the purpose of the food-color dyes is to allow you to see how fast certain plants are able to take up the dye pigments by capillary action. The dye molecules move through the water system of the plant in the sap and show up in the stem, leaves and flowers after a certain length of time. As water evaporates from leaves it lowers the pressure in the water channels of the stem so that more water is pulled up, and since the dye is dissolved in the water it is pulled up too. The dye does not affect the capillary action. It is just there so you can see the movement of sap. Adding more dye just makes the color darker in the plant.

Have you tested other kinds of flowers or celery stalks with the dye? If capillary action depends on evaporation of water from leaves [transpiration] then you would predict that a stem that has more leaves on it might have more rapid capillary action than one without leaves. In fact, you could test that by comparing two of the same kind of stems with the leaves cut off one of them.

Here are some websites that might be useful:

http://water.usgs.gov/edu/capillaryaction.html
http://water.usgs.gov/edu/watercycletranspiration.html
http://www.wikihow.com/Dye-Flowers
http://chemistry.about.com/od/colorchem ... lowers.htm

I hope this helps. If you have more questions, let us know.

Sybee