7 (a) Paper chromatography is a technique that can be used to separate and identify different chloroplast pigments.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2024). The mark or mark type is shown in brackets.

1. 1 calculate Rf value(s) ;
2. 2 (Rf = ) distance moved by pigment (from baseline) / distance moved by solvent (from baseline) ;
3. 3 compare with, known / standard / table, values ;
4. any three from:
5. 1 absorb light wavelengths not absorbed by, reaction centre / primary pigment / chlorophyll a ; A harvest
6. 2 so extend the range of wavelengths absorbed ;
7. 3 pass energy to, reaction centre / primary pigment / chlorophyll a ;
8. 4 ref. to accessory pigments ;
9. any seven from:
10. 1 carbon dioxide, reacts / combines, with, ribulose bisphosphate / RuBP ;
11. 2 (catalysed by) rubisco ;
12. 3 ref. to carbon (dioxide) fixation ;
13. 4 unstable 6C compound ;
14. 5 forms 2 (molecules of) glycerate 3-phosphate / GP ;
15. 6 glycerate 3-phosphate / GP, reduced to, triose phosphate / TP ;
16. 7 by reduced NADP and ATP ;
17. 8 triose phosphate / TP, used to regenerate RuBP ;
18. 9 glycerate 3-phosphate / GP, forms amino acids ;
19. 10 (some) TP forms, (named) hexoses / sucrose / maltose / starch / cellulose / glycerol / lipids / amino acids ;
20. 11 ref. to Calvin cycle ;