TOPIC 5 CELLULAR RESPIRATION

Which of the following statements about the electron transport chain is TRUE?

I For every NADH, 3 ATP molecules are produced

II For every FADH2, 2 ATP molecules are produced

III It occurs on the outer membrane of the mitochondria

IV Last electron of hydrogen atom is the oxygen molecule

• I, II and III

• I, II and IV

• I, III and IV

• II, III and IV

• I, II, III and IV

The following reaction occurs in cells during cellular respiration. Which of the following statements are TRUE about the reaction.

I The reaction occurs in the cytoplasm of cells

II Oxygen is not required
III 2H+ are released and accepted by NAD+

IV ATP is used
V Carbon dioxide is released

• I and III

• II and V

• III and V

• I, II and IV

• II, III and V

Which of the following protein complexes on the inner membrane of the mitochondrion function as a protein pump?

I NADH dehydrogenase

II Succinate dehydrogenase

III Cytochrome C reductase

IV Cytochrome C oxidase

V ATP synthase

• I, II and III

• I, III and IV

• II, III and IV

• I, III and V

• II, III and V

Oxidative phosphorylation is the

• addition of phosphate to ADP using energy gained by transferring electrons along a chain of carriers.

• addition of phosphate to ADP using energy gained by transferring electrons between chlorophyll molecules.

• addition of phosphate to glucose in the first step of glycolysis.

• removal of phosphate from ATP with the release of energy for work within the cell.

• transfer of phosphate from ATP to GP (PGA) in photosynthesis

The diagram summarizes the pathway of glucose breakdown. Which steps result in a net increase of ATP?

• 1 and 3

• 1 and 4

• 2 and 4

• 2 and 5

• 3 and 5

The diagram shows some of the reactions following glycolysis during aerobic respiration. How many carbon atoms are in each of the substances S, T and U?

• S - 2

  T - 5

  U - 3

• S - 2

  T - 6

  U - 4

• S - 3

  T - 4

  U - 6

• S - 3

  T - 6

  U - 4

• S - 6

  T - 3

  U - 3

Which substances enter and leave a mitochondrion during aerobic respiration?

• Enters: acetyl CoA

  Leaves: carbon dioxide

• Enters: ADP

  Leaves: lactate

• Enters: glucose

  Leaves: reduced NAD

• Enters: pyruvate

  Leaves: ATP

What happens to most of the reduced NAD molecules in cell metabolism?

• They act as oxidising agents in glycolysis.

• They are oxidised in mitachondrial ATP formation.

• They are oxidised in the Calvin Cycle.

• They combine with succinic acid as part of the Krebs cycle.

What will become of all the carbons from the glucose molecule after it is completely oxidised?

• Pyruvate

• Carbohydrate

• Carbon dioxide

• Acetyl-Coenzyme

Which of the following statement is TRUE in Krebs Cycle?

• Acetyl CoA combines with malate to form citrate

• Succinate is oxidised to fumarate

• Isocitrate is reduced to form α-ketoglutarate

• Malate is reduced to form oxaloacetate and NAD+ is reduced to NADH