Arrange the following events in a correct order that explains the pressure flow of materials in the phloem.

1. Glucose is converted into sucrose.
2. Sucrose moves into the sieve tube cells by active transport.
3. Water moves from xylem into phloem by osmosis.
4. Hypertonic condition is created in phloem.
5. Leaf cells produce sugar by photosynthesis.
6. As osmotic pressure builds up, phloem sap moves to areas of lower pressure.

The correct option is D 5 - 1 - 2 - 4 - 3 - 6
Food is transported by phloem from a source (part of a plant that synthesis food) to a sink (part that needs or stores food) in these steps:

$\bullet$ Leaf cells produce sugar by photosynthesis.
$\bullet$ Glucose prepared at source is converted into sucrose.
$\bullet$ Sucrose moves into the companion cells, then into the sieve tube cells by active transport.
$\bullet$ This creates a hypertonic condition in the phloem.
$\bullet$ As a result, water from the adjacent xylem tissue moves into the phloem by osmosis.
$\bullet$ As osmotic pressure builds up, the phloem sap moves to areas of lower pressure.
$\bullet$ As sugars are removed, the osmotic pressure decreases and water moves out of the phloem.