Question

Which of the following is a correct statement about a difference between xylem and phloem transport? A. Active transport moves xylem sap but not phloem sap. B. Xylem sap moves from sugar source to sink, but phloem sap does not. C. Phloem carries water and minerals; xylem carries organic molecules. D. Xylem sap moves up; phloem sap moves up or down. E. Transpiration moves phloem sap but not xylem sap.

Answer 1

Xylem sap moves up; phloem sap moves up or down.

Step-by-step explanation:

The direction of the movement of water and minerals in the xylem is always upward from roots to the upper plant parts. Roots absorb water and minerals from soil which in turn are moved upward towards stem, flowers, fruits, and seeds.

On the other hand, the movement of sugars through phloem occurs from source to sink tissues. During the growing season, leaves manufacture sugars and phloem transport them to the other non-photosynthesizing parts. A sink tissue may serve as a source of nutrients under certain conditions such as the death of the plant part. Therefore, the direction of the movement of sugars through the phloem may be upward or downward.