

MCQOPTIONS
This section includes 28 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.
1. |
The FADH and NADH produced by the oxidation of one acetyl-CoA results in the synthesis of about- |
A. | 3 ATPs |
B. | 6 ATPs |
C. | 11 ATPs |
D. | 15 ATPs |
Answer» D. 15 ATPs | |
2. |
Cholesterol can be synthesized in |
A. | pancreas |
B. | intestine |
C. | liver |
D. | cell membrane |
Answer» D. cell membrane | |
3. |
The catabolism of sugars and fatty acids is similar because |
A. | both of these compounds are funnelled through the TC A/citric acid cycle |
B. | both of these compounds generate redox energy during catabolism |
C. | both of these compounds generate chemical energy during catabolism |
D. | all of the above |
Answer» B. both of these compounds generate redox energy during catabolism | |
4. |
Which one of the following is not the intermediate of Kreb's cycle? |
A. | Isocitrate |
B. | Succinate |
C. | Fumarate |
D. | Stearate |
Answer» E. | |
5. |
Which one is not the main protein in electron transport chain? |
A. | NADH dehydrogenase |
B. | Cytochrome bc1 complex |
C. | Cytochrome oxidase |
D. | Citrate synthease |
Answer» E. | |
6. |
Important function of cholesterol is to |
A. | modulate fluidity |
B. | enhance blood circulation |
C. | prevent bile salts formation |
D. | None of these |
Answer» B. enhance blood circulation | |
7. |
The enzymes of the TCA cycle in a eukaryotic cell are located in the |
A. | nucleus |
B. | mitochondria |
C. | plasma membrane |
D. | lysosomal bodies |
Answer» C. plasma membrane | |
8. |
Citric acid cycle occurs in |
A. | cytoplasm |
B. | mitochondria |
C. | endoplasmic reticulum |
D. | golgi bodies |
Answer» C. endoplasmic reticulum | |
9. |
How many ATPs are produced during citric acid cycle? |
A. | 10 |
B. | 13 |
C. | 12 |
D. | 8 |
Answer» D. 8 | |
10. |
During cellular respiration, most of the ATP made, is generated by |
A. | oxidative phosphorylation |
B. | photophosphorylation |
C. | glycolysis |
D. | substrate-level phosphorylation |
Answer» B. photophosphorylation | |
11. |
Standard redox potential for a substance is measured under standard condition and is expressed as |
A. | mili-Ampere |
B. | Volt |
C. | without unit |
D. | Ohm |
Answer» C. without unit | |
12. |
The end product of glycolysis is pyruvate, which enters the citric acid cycle after being converted to |
A. | acetic acid |
B. | acetyl-CoA |
C. | acetaldehyde |
D. | none of these |
Answer» C. acetaldehyde | |
13. |
The FADH2 and NADH produced by the oxidation of one acetyl-CoA results in the synthesis of about- |
A. | 3 ATPs |
B. | 6 ATPs |
C. | 11 ATPs |
D. | 15 ATPs |
Answer» D. 15 ATPs | |
14. |
In eukaryotes, electron transport occurs in |
A. | membranes and mitochondria |
B. | endoplasmic reticulum |
C. | cytoplasm |
D. | all of the above |
Answer» B. endoplasmic reticulum | |
15. |
Energy that is released from glucose during respiration but not transferred to ATP bonds can be detected as |
A. | CO |
B. | <sub>2</sub> |
C. | AMP |
D. | ADP |
E. | heat |
Answer» E. heat | |
16. |
Cholesterol can be synthesized de novo in |
A. | pancreas |
B. | intestine |
C. | liver |
D. | cell membrane |
Answer» D. cell membrane | |
17. |
Most multi-cellular organisms obtain energy for the synthesis of ATP during oxidative phosphorylation from |
A. | high energy phosphate compounds |
B. | a proton gradient across the inner mitochondrial membrane |
C. | a proton gradient across the cell membrane |
D. | a proton gradient across the outer mitochondrial membrane |
Answer» C. a proton gradient across the cell membrane | |
18. |
A positive redox potential means substance has |
A. | lower affinity for electron |
B. | higher affinity for electron |
C. | lower affinity for proton |
D. | higher affinity for proton |
Answer» C. lower affinity for proton | |
19. |
How many molecules of ATPs are synthesized per NADH oxidation? |
A. | 2 |
B. | 1 |
C. | 3 |
D. | 4 |
Answer» D. 4 | |
20. |
Why is the TCA cycle the central pathway of metabolism of the cell? |
A. | It occurs in the center of the cell |
B. | Its intermediates are commonly used by other metabolic reactions |
C. | All other metabolic pathways depend upon it |
D. | None of the above |
Answer» C. All other metabolic pathways depend upon it | |
21. |
Malate-asparatate shuttle operates in |
A. | lungs and liver |
B. | heart and liver |
C. | pancreas and liver |
D. | none of these |
Answer» C. pancreas and liver | |
22. |
Oxidation of a molecule involves |
A. | gain of electron |
B. | loss of electron |
C. | gain of proton |
D. | loss of proton |
Answer» C. gain of proton | |
23. |
Which of the following enzyme does not take part in the TCA cycle? |
A. | Citrate synthase |
B. | Iso-citrate dehydrogenase |
C. | Pyruvate dehydrogenase |
D. | Malate dehydrogenase |
Answer» D. Malate dehydrogenase | |
24. |
The first intermediate in TCA cycle is |
A. | succinate |
B. | fumerate |
C. | citrate |
D. | malate |
Answer» D. malate | |
25. |
Most of the enzymes of the citric acid cycle in a eukaryotic cell are located in the |
A. | inner mitochondrial membrane |
B. | cytosol |
C. | mitochondrial matrix |
D. | intermembrane space |
Answer» D. intermembrane space | |
26. |
Which of the following is involved in energy production? |
A. | Generation of proton gradients across membranes |
B. | Transport of electrons on organic molecules |
C. | Conversion of compounds with high energy to those of low energy |
D. | All of the above |
Answer» E. | |
27. |
In what form does the product of glycolysis enter the TCA cycle? |
A. | AcetylCoA |
B. | Pyruvate |
C. | NADH |
D. | Glucose |
Answer» B. Pyruvate | |
28. |
To stop ATP synthesis which chemical is generally used? |
A. | DNSA |
B. | 2,4 dinitrophenol |
C. | DDT |
D. | None of the chemical can stop ATP synthesis |
Answer» C. DDT | |