During the germination of barley seeds, amylase is produced.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2021). The mark or mark type is shown in brackets.

1. [1] (a) seed / embryo, absorbs water ;
2. [1] (a) (stimulates) embryo to produce gibberellin ;
3. [1] (a) gibberellin moves to aleurone layer;
4. [1] (a) gene coding for amylase, expressed / transcribed ;
5. [1] (a) translation of mRNA (to produce amylase);
6. [1] (a) AVP; e.g. gibberellin binds to receptor / ref. destruction of DELLA protein
7. [1] (b)(i) endosperm;
8. [1] (b)(ii) amylase activity increases ;
9. [1] (b)(ii) as (seeds) produce more amylase ;
10. [1] (b)(ii) percentage of starch decreases ;
11. [1] (b)(ii) amylase, hydrolyses / breaks down, starch ;
12. [1] (b)(ii) idea of a change at an increasing rate (for either) ; A exponential change
13. [1] (b)(ii) data quote: amylase or starch at two different days ;
14. [1] (c)(i) enzyme, denatured / deactivated / inactivated;
15. [1] (c)(i) changes, tertiary structure / 3D shape, of amylase ; A enzyme
16. [1] (c)(i) changes shape of active site;
17. [1] (c)(i) active site, no longer complementary / does not bind, to starch / substrate or no, ESC / enzyme-substrate complexes, formed;
18. [1] (c)(i) AVP; e.g. removes water from embryo for gibberellin synthesis / removes water from endosperm for hydrolytic reactions
19. [1] (c)(ii) stops, sugars / glucose, from being used ; ora
20. [1] (c)(ii) ensures (enough) sugars for beer production ;