RS-T06-Q12 · 无氧呼吸「乳酸 / 酒精发酵」

先自己写完再对答案；卡住的地方回看这段讲解（公开课时间码 24:20–26:40）

来源 9700_s12_qp_42.pdf → 9700_s12_ms_42.pdf　|　小问：全部小问

触发题型：看到 anaerobic / 问哺乳动物 vs 酵母 / 问为什么必须再生 NAD

✅ Mark Scheme 得分点（原文）

逐条计分：n 分写 n 条；红字为考官明确不接受（Do not accept）

(a)

1. gnore ref. to energy currency alone
2. 1.
3. ATP provides energy (linked to either) ;
4. i
5. active transport
6. 2.
7. movement against concentration gradient ;
8. ignore pump
9. 3.
10. carrier / transport, protein (in membrane) ;
11. 4.
12. binds to (specific) ion ;
13. 5.
14. protein changes shape ;
15. anabolic reactions
16. 6.
17. synthesis of complex substances from simpler ones ;
18. 7.
19. starch / cellulose / glycogen, from, monosaccharides / named monosaccharides / named
20. sugar ;
21. 8.
22. glycosidic bonds ;
23. 9.
24. lipid / triglyceride, from fatty acids and glycerol ;
25. 10. ester bonds ;
26. 11. polypeptides / proteins, from amino acids ;
27. 12. peptide bonds ;
28. 13. other named polymer from suitable monomer ;
29. 5 max
30. 14. appropriate named bond ;
31. [7 max]
32. general

(b)

1. A
2. 15. reduced NAD produced in glycolysis
3. glycolysis described
4. 16. small amount of ATP produced in glycolysis ;
5. in yeast cells
6. 17. pyruvate converted to ethanal ;
7. 18.
8. carbon dioxide released / decarboxylation
9. 19. ethanal, reduced / accepts H ;
10. 20. by reduced NAD ;
11. 21. ethanol formed ;
12. in mammalian cells
13. 22. pyruvate converted to lactate ;
14. 23. by reduced NAD
15. Mark Scheme: Teachers’ version
16. 24. in, liver / muscle, cells ;
17. 25. AVP ;;
18. 26. e.g. reversible in mammal / irreversible in yeast / single step in mammal / more than 1 in
19. yeast / reoxidised NAD allows glycolysis to continue / named enzyme
20. either
21. or
22. only award
23. mp19
24. mp23
25. [8 max]