5. Cellular Respiration
CHAPTER 5: CELLULAR RESPIRATION
1. FIGURE 1 represents two main stages in cellular respiration.
FIGURE 1
(a) Name the reaction that occurs at step 2, 3 and 4 and the TWO by-products of
the reaction. [3 marks]
- Oxidative decarboxylation
- NADH
- CO2
(b) At which step does the substrate level phosphorylation occur, and how
many ATP(s) are produced at this step from one molecule of glucose?
[2 marks]
- Step 5 OR - Step 1
- 2 ATP - 4 ATP
*ATP dependent on step.
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(c) State what happens to the hydrogen produced at step 6 [2 marks]
- Hydrogen bind with FAD
- To form FADH2
(d) Identify compound X. [1 mark]
-Acetyl CoA
(e) The reduced co-enzyme produced in step 1 will enter the electron transport
system. What is the reduced co-enzyme? [1 mark] NADH
(f) What is the reaction involved in the production of ATP when the reduced
co-enzyme in (e) enters the electron transport system? [1 mark]
Oxidative phosphorylation
PSPM II 2008/2009
2. FIGURE 2 shows some of the steps involved in cellular respiration in muscle tissues.
Glucose
Step P
Fructose-6-phosphate
Step Q
Fructose-1,6-bisphosphate
Step R
Glyceraldehyde-3-phosphate
Step S
1,3-bisphosphoglycerate
FIGURE 2
(a) Name the process which involves the above steps. [1 mark]
Glycolysis
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(b) In which TWO steps are ATPs being used? Why is ATP used? [3 marks]
- P/ From Glucose to Glucose- 6-phosphate
- Q/ From Fructose-6-phosphate toFructose-1,6-bisphosphate
- Increase the energy level of molecule// phosphorylate the molecule
(c) Name the enzymes involved in steps P and Q. [2 marks]
Step P: hexokinase
Step Q: phosphofructokinase
(d) In which step is NADH produced? State the function of NADH. [2 marks]
- Step S/ Glyceraldehyde-3-phosphate)
- Electron carrier/ reducing agent to the electron transport chain
(e) How many molecules of NADH and pyruvate are produced from one molecule
of 1,3-bisphosphoglycerate ? [2 marks]
0 NADH
1 Pyruvate
PSPM II 2010/2011
3. FIGURE 3 shows a schematic diagram of cellular respiration.
FIGURE 3
(a) Name the type of cellular respiration shown in FIGURE 7. [1 mark]
- Fermentation
(b) (i)State in what condition does the cellular respiration in 6(a) to
occur. [1 mark]
- In the absence of oxygen
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CHAPTER 5: CELLULAR RESPIRATION
1. FIGURE 1 represents two main stages in cellular respiration.
FIGURE 1
(a) Name the reaction that occurs at step 2, 3 and 4 and the TWO by-products of
the reaction. [3 marks]
- Oxidative decarboxylation
- NADH
- CO2
(b) At which step does the substrate level phosphorylation occur, and how
many ATP(s) are produced at this step from one molecule of glucose?
[2 marks]
- Step 5 OR - Step 1
- 2 ATP - 4 ATP
*ATP dependent on step.
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,5. Cellular Respiration Collection of Exam Papers
(c) State what happens to the hydrogen produced at step 6 [2 marks]
- Hydrogen bind with FAD
- To form FADH2
(d) Identify compound X. [1 mark]
-Acetyl CoA
(e) The reduced co-enzyme produced in step 1 will enter the electron transport
system. What is the reduced co-enzyme? [1 mark] NADH
(f) What is the reaction involved in the production of ATP when the reduced
co-enzyme in (e) enters the electron transport system? [1 mark]
Oxidative phosphorylation
PSPM II 2008/2009
2. FIGURE 2 shows some of the steps involved in cellular respiration in muscle tissues.
Glucose
Step P
Fructose-6-phosphate
Step Q
Fructose-1,6-bisphosphate
Step R
Glyceraldehyde-3-phosphate
Step S
1,3-bisphosphoglycerate
FIGURE 2
(a) Name the process which involves the above steps. [1 mark]
Glycolysis
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(b) In which TWO steps are ATPs being used? Why is ATP used? [3 marks]
- P/ From Glucose to Glucose- 6-phosphate
- Q/ From Fructose-6-phosphate toFructose-1,6-bisphosphate
- Increase the energy level of molecule// phosphorylate the molecule
(c) Name the enzymes involved in steps P and Q. [2 marks]
Step P: hexokinase
Step Q: phosphofructokinase
(d) In which step is NADH produced? State the function of NADH. [2 marks]
- Step S/ Glyceraldehyde-3-phosphate)
- Electron carrier/ reducing agent to the electron transport chain
(e) How many molecules of NADH and pyruvate are produced from one molecule
of 1,3-bisphosphoglycerate ? [2 marks]
0 NADH
1 Pyruvate
PSPM II 2010/2011
3. FIGURE 3 shows a schematic diagram of cellular respiration.
FIGURE 3
(a) Name the type of cellular respiration shown in FIGURE 7. [1 mark]
- Fermentation
(b) (i)State in what condition does the cellular respiration in 6(a) to
occur. [1 mark]
- In the absence of oxygen
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