Forwarded from Dr.Shimaa Munther Biochemistry MCQ
السلام عليكم ادناه اسئلة المحاضرات الخاصة ب
Citric Acid Cycle
Citric Acid Cycle
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
A single molecule of glucose generates _________ molecules of acetyl CoA, which enters the Krebs cycle.
Anonymous Quiz
12%
4
9%
3
62%
2
17%
1
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Krebs cycle occurs in aerobic respiration due to
Anonymous Quiz
40%
Electron transport chain requires aerobic conditions to operate
6%
Oxygen is a reactant
4%
Oxygen has a catalytic function
50%
All of the above
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Acetyl CoA is formed from pyruvate by__________ reaction
Anonymous Quiz
28%
Dehydration
7%
Reduction
10%
Dephosphorylation
55%
Oxidative decarboxylation
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following is not formed during the Krebs cycle?
Anonymous Quiz
76%
Lactate
4%
Isocitrate
4%
Succinate
16%
Both (a) and (b)
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
The entry of pyruvate into the TCA cycle is inhibited by the presence of a high cellular concentration of
Anonymous Quiz
23%
Pyruvate
39%
NADH
17%
AMP
22%
Coenzyme A
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
FAD is reduced in which of the reaction of the Kreb’s cycle?
Anonymous Quiz
9%
Isocitrate to oxaloacetate
59%
Succinate to fumarate
15%
Fumarate to malate
17%
Succinyl CoA to Succinate
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
The Product Essential for Oxidative Phosphorylation in the Krebs Cycle is _______
Anonymous Quiz
16%
NADPH and ATP
51%
NADH and FADH2
12%
CO2 and oxaloacetate
20%
Acetyl CoA
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
The conversion of pyruvate to acetyl CoA is catalyzed by the enzyme pyruvate dehydrogenase. In this reaction
Anonymous Quiz
15%
NADPH is oxidized to NAD
50%
NAD is reduced to NADH
12%
NADP is reduced to NADPH
22%
NADH is oxidized to NAD
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following is false regarding enzyme pyruvate dehydrogenase?
Anonymous Quiz
15%
It is a multi-enzyme complex
26%
It requires thiamine, flavin, and nicotine vitamin co-enzymes
18%
The pyruvate dehydrogenase complex is a mitochondrial enzyme
40%
It catalyzes the reversible reaction (conversion of pyruvate to acetyl CoA)
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Pyruvate dehydrogenase is an important regulatory enzyme that senses the energy status of the cells. Which of the following is NOT the regulator of pyruvate dehydrogenase?
Anonymous Quiz
10%
NADH
16%
Acetyl CoA
22%
ATP
52%
Citrate
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following enzyme catalyzes substrate-level phosphorylation i.e conversion of GDP to GTP?
Anonymous Quiz
10%
Malate dehydrogenase
69%
Succinyl CoA thiokinase
9%
Fumarase
13%
Isocitrate dehydrogenase
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following is not the irreversible reaction of Kreb's cycle?
Anonymous Quiz
13%
Isocitrate dehydrogenase
31%
Citrate synthas
23%
Alpha-ketoglutarate dehydrogenase
33%
Malate dehydrogenase
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
TCA cycle is also known as the amphibolic pathway (function both in oxidative and synthetic processes). Which of the following is a correct statement regarding
Anonymous Quiz
14%
Alpha-ketoglutarate plays a critical role in amino acid metabolism
17%
Oxaloacetate is an intermediate for gluconeogenesis and fatty acid synthesis
8%
Succinyl CoA is involved in ketone body metabolism
61%
All of the above
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following metabolic intermediate activates the TCA cycle?
Anonymous Quiz
28%
High NADH/NAD
28%
High ADP/ATP ratio
35%
Oxaloacetate
9%
None of the above
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
What is the Other name of Krebs Cycle
Anonymous Quiz
4%
EMP pathway
3%
Glycolate Cycle
4%
Glyoxylate Cycle
89%
Citric acid cycle
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Kreb’s cycle begins with the creation of six carbon compounds as a result of a reaction between two carbon compounds namely
Anonymous Poll
11%
Succinic Acid and pyruvic acid
7%
Maleic acid and acetyl CoA
7%
Fumaric acid and Pyruvic acid
75%
Acetyl CoA and Oxaloacetic Acid
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Why is the TCA cycle the central pathway of metabolism of the cell?
Anonymous Quiz
55%
Its intermediates are commonly used by other metabolic reactions
20%
All other metabolic pathways depend upon it
15%
It occurs in the center of the cell
11%
None of the above
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Niacin (B3) is important in all the following krebs reactions except:
Anonymous Quiz
12%
Isocitrate dehydrogenase
19%
Malate dehydrogenase
17%
α -ketoglutarate dehydrogenase
52%
Succinate dehydrogenase
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which of the following is NOT a site for regulation of the citric acid cycle?
Anonymous Quiz
17%
Citrate synthase
10%
Isocitrate dehydrogenase
63%
Pyruvate dehydrogenase
10%
α-ketoglutarate dehydrogenase
Forwarded from Dr.Shimaa Munther Biochemistry MCQ
Which enzyme in the citric acid cycle is inhibited by ATP?
Anonymous Quiz
30%
Citrate synthase
17%
Fumarase
27%
α-ketoglutarate dehydrogenase
26%
Isocitrate dehydrogenase