Movement of Fluids in the Phloem

Translocation

movement of sugars (and other organic molecules) in plants within the phloem

What are the other organic molecules that are moved in the phloem?

plant hormones, amino acids, and mRNA

What is the main sugar moved by translocation?

Sucrose

What types of sugar is sucrose?

A disaccharide made of glucose and fructose

Which direction does fluid move in the phloem?

Both directions

What do the companion cells need to load into sieve cells?

Energy and co-transport

How are sugars moved within the phloem?

They are moved by bulk flow

Source cell

high concentration of sugar

ex: leaves, bulbs, root, tubers

(where sugar is coming from)

Sink cell

cell that needs energy or stores the sugar

(where the sugar is going to)

The sink cells can be bulbs, roots, buds, seeds, or fruit depending on ….

the season