Biology · May / June 2026 · Paper 41 · Question 3

any five from:

1

ref. to translocation ;

2

carbon dioxide (containing 14C) is taken into the leaf (by diffusion) ; 3

correct ref. to photosynthesis, occurring / described ;

4

sucrose / glucose / amino acids, contains, the radioactive carbon / 14C ; 5

glucose converted to sucrose ;

6

sucrose / amino acids / radioactive carbon / 14C , is transported in the phloem ;

7

(sucrose / amino acids / radioactive carbon / 14C) transported / AW, to the root OR not, transported / AW, to the top of stem ;

8

leaf acts as a source and roots act as a sink ;

acts as a control ;

plus

to show where (sucrose / amino acids / radioactive carbon / 14C) is found when phloem is intact ;

OR

to see if the effect is due to ringing ;

OR

to compare with the effect of ringing ;

reduces (rate of transpiration) ;

(because there are) fewer stomata / water is lost through stomata ;

no effect (on the rate of transpiration) ;

(transpiration) occurs through xylem / xylem transports water ;

vascular bundles ;

xylem ;