Arrange the following five events in an order that explains the mass flow of materials in the phloem.
1) Water diffuses into the sieve tubes.
2) Leaf cells produce sugar by photosynthesis.
3) Solutes are actively transported into sieve tubes.
4) Sugar is transported from cell to cell in the leaf.
5) Sugar moves down the stem.

Question

Quizplus · Accepted Answer

The correct sequence starts with photosynthesis in the leaves (2), followed by sugar being transported from cell to cell within the leaf (4). Then, solutes (including the sugars) are actively transported into the sieve tubes of the phloem (3), causing water to diffuse into the sieve tubes due to osmotic pressure (1), which finally results in the sugar (along with other solutes) moving down the stem (5).

Arrange the Following Five Events in an Order That Explains