Question

Xylem transports sap upwards only whereas pholem transports food in both directions, Why do you think there is a difference?

Answer 1

Xylem transports water and minerals from the roots to other parts of the plant. It transports sap upwards only, as all other parts of the plant are in upward direction. Phloem transports food prepared by the leaves in both upward and downward directions, as each part of the plant, whether upward or downward, needs food.