Biochemistry online test on “ATP Synthesis – 2”.
1. The proposal of the chemiosmotic hypothesis was by ____________
A. Peter D. Mitchell
B. Charles Darwin
C. Mendele
D. Alfred Russell
Answer: A
Clarification: Peter D. Mitchell was the one to propose a chemiosmotic hypothesis.
2. ATP synthesis by chemiosmosis is by ____________
A. ATP dehydrogenase
B. Gyrase
C. ATP synthase
D. Dehydrogenase
Answer: C
Clarification: ATP synthase synthesizes ATP by chemiosmosis.
3. The measure of potential energy stored as a combination of proton and voltage gradients across membrane is termed as ____________
A. Proton motive force
B. Electron motive force
C. Molecule motive force
D. Ion motive force
Answer: A
Clarification: The measure of potential energy stored as a combination of proton and voltage gradients across membrane is termed as proton motive force.
4. The transport of acyl co-A for oxidation using a shuttle involves the formation of the intermediate ____________
A. Acyl coenzyme A
B. 3 acetyl co-A
C. Acyl cartinine
D. None
Answer: C
Clarification: The intermediate acyl cartinine is formed in the transport of acyl co-A for oxidation using a shuttle.
5. Three identical β subunits of the F1 complex during ATP synthesis have ____________
A. Different affinities for ATP and ADP
B. Similar affinities for ADP and ATP
C. Different affinities for ADP but not ATP
D. Different affinities for ATP but not ADP
Answer: A
Clarification: The conformational differences among β subunits extend to differences in their ATP/ADP-binding sites.
6. The acyl co-A formed in the cytosol is transported to ____________
A. Mitochondrial matrix
B. Microsomes
C. ER
D. Remains in cytosol
Answer: A
Clarification: The acyl co-A formed in the cytosol is transported to mitochondrial matrix.
7. Every cycle of β-oxidation produces ____________
A. 1 FAD, 1 NAD+ and 2 CO2 molecules
B. 1 FADH2, 1 NADH and 1 acetyl co-A
C. 1 FADH2, 1 NAD+ and 1 acetyl co-A
D. 1 FAD, 1 NADH and 2 CO2 molecules
Answer: B
Clarification: Every cycle of β-oxidation produces 1 FADH2, 1 NADH and 1 acetyl co-A.
8. Membrane potential and the proton gradient ____________
A. Cancel one another when uncouplers are present
B. Reinforce one another when respiratory inhibitors are present
C. Are sufficient, separately to make ATP from ADP + Pi
D. Are required to make ATP
Answer: D
Clarification: Membrane potential and proton gradient are both required to make ATP.
9. Long-chain fatty acids are oxidized step-wise in one carbon unit starting from ____________
A. Carboxyl end
B. Aliphatic end
C. Carboxyl and Aliphatic end
D. None of the mentioned
Answer: A
Clarification: Long-chain fatty acids are oxidized step-wise in one carbon unit starting from carboxyl end.
10. Maximum energy per gram on oxidation is yielded from ____________
A. Starch
B. Fat
C. Glycogen
D. Protein
Answer: B
Clarification: Fat yields maximum energy per gram on oxidation.