Homeostasis: how food is transported by phloem

Question 1

What is translocation

Answer 1

the transport of sucrose (glucose - glucose) and other organic molecules through the phloem of a plant

Question 2

What is the pressure-flow model

Answer 2

explains how organic molecules (surcrose) move from the source (leaf) to the sink (roots/stem) through phloem in a flowering plant. the sink is a storage area for sugars.

example: carrots, potatoes, and turnips are root vegetables that store sugars in their roots

Question 3

What are the 4 steps in translocation

Answer 3

1: glucose produced by photosynthesis in the leaf is converted to sucrose and then enters the phloem by active transport

2: water moves into the phloem by osmosis as a result of the increased concentration of sucrose. the movement of water leads to an increase in pressure in the phloem .

3: this creates a pressure gradient that pushes the sugar solution towards the sink for storage

4: sucrose is removed from the phloem by tissues in the plant stem and root. this causes the concentration of sucrose solution to fall, and therefore water moves out of the phloem as well. pressure in the phloem decreases