Transport in Plants

Question 1

What are the two main ways water moves through the root to the Xylem?

Answer 1

Symplast and Apoplast pathway

Question 2

What is the Symplast pathway?

Answer 2

This is the path where water moves through cytoplasm’s via connecting plasmodesmata

Question 3

What is the Apoplast pathway?

Answer 3

This is the path where water passes through spaces in the cell wall until reaching the casparian strip, then it follows the symplast pathway

Question 4

What is the definition for Translocation?

Answer 4

The transport of assimilates from source to sink

Question 5

Can you explain what active loading is in Translocation.

Answer 5

This is when the companion cell actively pumps H+ out of the cell so when a conc gradient is established the H+ moves back in via cotransport with Sucrose molecules

Question 6

After active loading what happens?

Answer 6

Sucrose molecules from the companion cell actively are moved into the sieve tubes. The high conc of sucrose lowers water potential

Question 7

What happens when water potential is low in the sieve tubes of the phloem?

Answer 7

Water moves in via osmosis from xylem creating high pressure.
The solutes (sucrose) reach the sink cell to be used up and water leaves the phloem via osmosis