Phloem Loading

Question 0

Symplastic:

Answer 0

Sugar moves through cells by plasmodesmata

Question 1

Apoplastic:

Answer 1

Sugar movement occurs from cell to cell through the plasmodesmata (within cytoplasm) mostly. When it gets to a companion cell it has to move through the cell wall (initially symplastic movement until companion cells) active

Question 2

Symplastic

1) Passive:
2) Polymer trapping model:

Answer 2

Passive: w/very actively growing sinks which keeps a high concentration gradient
Polymer Trapping Model: intermediary cell converts built up sucrose into raffinose to maintain concentration gradient for sucrose

Question 3

Assimilate Partitioning

Allocation:

Answer 3

The regulation of the distribution of fixed carbon.

1) Utilized: for metabolic purposes
2) Converted to sugars for transport
3) Storage: as starch —> converted

Question 4

Assimilate Partitioning

Partitioning:

Answer 4

Distribution of carbon/photosynthate within the plant. (where it transports)

1) Proximity: location to sink (closest)
2) Sink Strength: Ability of a sink to mobilize photosynthate towards itself

Question 5

Carbon Mobilization

Answer 5

G3P either goes to storage (Starch) or moves out to sucrose. The G3P in storage can then go to sucrose (@night). Then sucrose goes to ATP & NADPH production or moves on to phloem tissue to the sink