Question

matching
use the numbered items to match the pathway with the molecules generated.
each letter may be used more than once, and each molecule may have more than
one answer.

1. ____ glyceraldehyde 3-phosphate
2. ____ atp
3. ____ nadh
4. ____ nad⁺
5. ____ nadph
6. ____ glucose
7. ____ co₂
8. ____ ribose 5-phosphate
9. ____ pyruvic acid
10. ____ glucose 6-phosphate

a. glycolysis
b. pentose phosphate pathway
c. entner-doudoroff pathway
d. calvin-benson cycle
e. krebs cycle
f. electron transport chain
g. gluconeogenesis

Explanation:

To solve this matching problem, we analyze each molecule and the associated metabolic pathways:

1. Glyceraldehyde 3 - phosphate: Produced in Glycolysis (A), Pentose Phosphate Pathway (B), Entner - Doudoroff Pathway (C), and Calvin - Benson cycle (D) (for carbon fixation).
2. ATP: Generated in Glycolysis (A), Entner - Doudoroff Pathway (C), Krebs cycle (E), Electron transport chain (F), and used in Gluconeogenesis (G) but also produced in energy - yielding pathways. Also, Calvin - Benson cycle (D) uses ATP, but here we focus on production; main production pathways: A, C, E, F.
3. NADH: Produced in Glycolysis (A), Entner - Doudoroff Pathway (C), Krebs cycle (E).
4. NAD⁺: Regenerated in Electron transport chain (F) (oxidative phosphorylation) and Glycolysis (A, via fermentation - like steps), Entner - Doudoroff (C), Krebs (E) (redox reactions).
5. NADPH: Produced in Pentose Phosphate Pathway (B) and Calvin - Benson cycle (D) (for reductive biosynthesis and carbon fixation).
6. Glucose: Produced in Gluconeogenesis (G) (from non - carbohydrate precursors) and can be a product of Calvin - Benson cycle (D) (carbon fixation to glucose).
7. CO₂: Produced in Krebs cycle (E) (decarboxylation steps) and Pentose Phosphate Pathway (B) (oxidative phase), and released in Calvin - Benson cycle (D) is incorrect; Calvin fixes CO₂, so E, B (and sometimes others, but main here: E, B).
8. Ribose 5 - phosphate: Produced in Pentose Phosphate Pathway (B) (non - oxidative or oxidative phase).
9. Pyruvic acid: Produced in Glycolysis (A) and Entner - Doudoroff Pathway (C).
10. Glucose 6 - phosphate: Produced in Glycolysis (A, initial phosphorylation), Pentose Phosphate Pathway (B, starting molecule), Gluconeogenesis (G, final step to glucose - 6 - P), and Calvin - Benson cycle (D, intermediate in glucose synthesis).

Answer:

1. A, B, C, D
2. A, C, E, F
3. A, C, E
4. A, C, E, F
5. B, D
6. D, G
7. B, E
8. B
9. A, C
10. A, B, D, G