Transcloaction

Question 1

Describe the processes involved in the transport of sugars in plant stems.

Answer 1

(At source) sucrose is actively (transported) into the phloem/sieve element/tube;

Accept: ‘sugar/s’ for sucrose but reject other named sugars e.g. glucose.

Accept: co-transport (with H+ ions).

2. By companion/transfer cells;
3. Lowers water potential in phloem/sieve element/tube and water enters by osmosis;
4. (Produces) high (hydrostatic) pressure;

Accept: pressure gradient.

5. Mass flow/transport towards sink/roots/storage tissue;

Accept: sieve element/tube.

6. At sink/roots sugars are removed/unloaded;

Accept: at sink/roots sugars are used in respiration/stored.