Banana Strings

Life is full of mysteries, like what are the stringy bits attached to a freshly peeled banana? Good question.

The strings on a banana, which are so often picked off and thrown away, are known as “phloem bundles.” Phloem is a type of vascular tissue that helps distribute sugars and other goodies throughout a plant. They consist mainly of long tube-like cells called “sieve elements” or “SEs.”

In the process of becoming a living tube, SEs lose important cellular organs and would otherwise die if it were not for a special kind of cell known as a “companion cell” or “CC.” CCs, like a good companion, support the SEs and help keep them alive. Together, these buddy cells pass on nutrients from the leaves to elsewhere in the plant.

The phloem tissues that run the length of a banana are bundles of buddies that distribute sugars and other nutrients throughout the developing fruit, ensuring the development of a sweet, healthy treat. So if you want to enjoy a high-quality, tasty banana, I’m afraid there will always be strings attached.

Brian Rutter, PhD, is the cofounder of Hundredfold Video and plant biologist working for 2Blades at the University of Minnesota. Subscribe to our newsletter to receive our “Things About Things – Odd Facts About Plants” and video production tips in your inbox every month!

Works Cited:

Oparka, Karl J., and Robert Turgeon. "Sieve elements and companion cells—traffic control centers of the phloem." The Plant Cell 11, no. 4 (1999): 739-750.

Stiefvater, Sarah. “Banana strings (AKA phloem bundles) are actually really good for you." purewow.com, 10 July 2017, https://www.purewow.com/wellness/banana-strings-phloem-bundles.