Question

Describe experiments on:

To prove phloem conducts food.

Answer 1

Procedure: On a healthy potted plant, carefully remove a complete ring of bark around the stem. This removes the phloem tissue but leaves the deeper, inner xylem wood completely untouched.

Observation: After a couple of weeks, the bark immediately above the cut ring swells up noticeably, while the growth below the ring stalls, and the roots eventually weaken.

Conclusion: The swelling happens because organic food manufactured by the leaves travels downward through the phloem but gets blocked at the point of the cut. This proves that phloem tissue conducts food from the leaves to the rest of the plant.