Question

Please help me figure these out, and if you could explain why you got the answer you did that would be great, because I have an exam tomorrow! Thanks in advance.

1. Anaplerotic reactions __________.

A. produce oxaloacetate and malate to maintain constant levels of citric acid cycle intermediates

B. produce biotin needed by pyruvate carboxylase

C. recycle pantothenate used to make CoA

D. produce pyruvate and citrate to maintain constant levels of citric acid cycle intermediates

E. All of the above

2. Which of the following is incorrect about the carriers of the electron transport chain in mitochondria?

A. the iron atom of cyt c is reduced when it accepts electrons

B. cyt c is a peripheral membrane protein located on the matrix face of the inner mitochondrial membrane

C. coenzyme Q is a lipid soluble quinone which accepts electrons and protons from either complex I or II

D. complex I contains FMN as a component which accepts both electrons and protons

3. Which one of the following statements about photophosphorylation is false?

A. It can be uncoupled from electron flow by agents that dissipate the proton gradient.

B. The difference in pH between the luminal and stromal side of the thylakoid membrane is 3 pH units.

C. The reaction centers, electron carriers, and ATP-forming enzymes are located in the thylakoid membrane.

D. The number of ATPs formed per oxygen molecule is about three.

E. The luminal side of the thylakoid membrane has a higher pH than the stromal side.

4. Which of the following fatty acids would produce the most energy upon complete oxidation to CO₂?

A. palmitic (16:0)          B. stearic (18:0)         C. oleic (18:1)         D. linoleic (18:2)

5. What is the membrane soluble mobile carrier in the electron transport chain?

A. NADH              B. FADH₂                   C. ubiquinone             D. cytochrome c

6. What statement is incorrect about the mitochondrial ATP-synthesizing complex?

A. It contains a transmembrane proton channel.

B. It contains a spherical headpiece called F₁ located on the cytoplasmic side of the inner membrane.

C. It requires intact inner mitochondrial membranes to synthesize ATP.

D. The complex hydrolyzes ATP when the inner membranes are disrupted or leaky.

7. In the light reaction, the reducing agent and the oxidizing agent, respectively are:

A. H₂O and O₂       B. NADP⁺and NADPH C. H₂O and NADP⁺      D. ADP and ATP

8. Which statement is incorrect about the glycerolphosphate shuttle?

A. There are two distinct forms of glycerol 3-P dehydrogenase in cells

B. It results in the net transfer of electrons to the electron transport chain from NADH in the cytoplasm

C. glycerol 3-P is transported across the inner mitochondrial membrane into the matrix

D. electrons derived from this shuttle enter the electron transport chain at a protein complex containing an FAD linked enzyme

Thanks again!

Answer 1

1. E. all of the above.

Anaplerotic reactions are those which produce intermediates in a chemical reaction/ metabolic pathways/ biosynthetic reactions.