1. 9.2 Transport in the Phloem of Plants

2. Phloem
Vascular tissue that transports sugars and amino acids throughout the plant

5. Translocation
The process of moving organic material through the phloem
Uses energy in the form of active transport to carry organic material from source (location of synthesis) to sink (location of use)
Since there is active transport the tissue needs to be living. Therefore phloem is alive and functional at maturity.
However it is hollow to facilitate the movement of materials

6. Draw

7. Cells that make up Phloem
Sieve Tubes (hollow)
Companion cells (house mitochondria and nucleus which regulate products for both cell types)
Connected by
Plasmodesmata
(channels)

8. Cells that make up Phloem
Draw
Sieve Tubes (hollow)
Companion cells (house mitochondria and nucleus which regulate products for both cell types)
Connected by
Plasmodesmata
(channels)

9. Source of organic molecules
Leaves of plants (photosynthesis)
Underground roots and stems - store carbohydrates
Bulbs, tubers, storage roots
Act as the source but can also be sink
Therefore translocation can occur in all directions

11. Location Xylem and phloem lie adjacent to each other
Xylem and phloem lie adjacent to each other
Allows water to move easily
Sucrose typically moves into phloem
Osmotic gradient causes water to move into phloem
Organic materials move from source to sink from areas of high concentration to areas of low concentration
Sucrose: transport sugar molecule
Draw

12. Dehydration Synthesis What is a sucrose molecule made of?

13. Hydrolysis of Sucrose

14. Starch What is a starch molecule made of?

15.
1:39 - 4

17. Turgor Pressure The water pressure inside plant cells
Can also be called hydrostatic pressure

18. Xylem and phloem in Dicot root and stem cross sections

19. Draw: Dicot and Monocot Stems

20. Draw

22. Vascular tissue Vascular bundle: Holds the xylem and phloem
Vascular cambium: located between the xylem and phloem
Made of undifferentiated cells to become either xylem or phloem

23. Draw

24. Transpiration Vs. Translocation
Passive: water diffuses into the xylem and evaporates from the leaves
Active: sucrose and amino acids are pumped into the phloem
Transports water and minerals
Transports sucrose, amino acids and hormones
Consists of vessel elements and tracheids
Consists of sieve tubes and companion cells
Dead at functional maturity
Alive at functional maturity
Moves water and minerals from the roots to the shoot (one direction of travel)
Moves organic molecules from the source (leaves or storage organ) to the sink (growing plan structure: fruits, seeds, roots)