CIE iGCSE Co-Ordinated Science B6.2 Leaf structure Exam Style Questions Paper 4
Question
(a) Fig. 4.1 shows a cross-section of a leaf.
(i) State the letter in Fig. 4.1 that identifies the cells that control loss of water vapour from a leaf.
(ii) State the names of the parts labelled A and B in Fig. 4.1.
(iii) Describe two ways in which the part labelled G in Fig. 4.1 is adapted for photosynthesis.
(b) Carbohydrates produced by photosynthesis are transported to areas of the plant described as sinks.
(i) Describe how the carbohydrates are transported to the sinks.
(ii) State two uses of carbohydrates in sinks.
(c) Carbon dioxide diffuses into a leaf during gas exchange.
State two factors which increase the rate of diffusion during gas exchange.
▶️Answer/Explanation
Ans :
4(a)(i) D ;
4(a)(ii) A (upper) epidermis ;
B cuticle ;
4(a)(iii) any two from:
contain lots of chloroplasts ;
located at the top of leaf ;
tightly packed / column shaped ;
4(b)(i) as sucrose ;
by translocation ;
in the phloem ;
4(b)(ii) any two from:
storage ;
respiration ;
growth ;
4(c) any two from:
increased surface area ;
increased temperature ;
steeper concentration gradient ;
shorter diffusion distance ;