Respiration in Plants MCQs

Consider the net ATP yield if the glycerol phosphate shuttle is used (2 ATP per cytosolic NADH):

I. Two glycolytic NADH yield 4 ATP instead of 6.
II. Total ATP yield becomes 36 ATP per glucose.
III. Total ATP yield remains 38 ATP regardless of shuttle used.
IV. Mitochondrial NADH yield remains unchanged.

Which statements are correct?

Statement analysis regarding utility of respiratory balance sheet calculations:

I. They help appreciate the efficiency of energy extraction in living systems.
II. They provide exact ATP production in intact living cells.
III. They allow comparison between metabolic pathways.
IV. They are theoretical calculations based on specific assumptions.

Which statements are correct?

How many total ATP molecules are produced purely via Substrate-Level Phosphorylation during complete aerobic respiration of one Glucose?

I. 2 ATP in Glycolysis (net).
II. 2 GTP (≈2 ATP) in TCA Cycle.
III. Total = 4 ATP molecules directly via substrate-level phosphorylation.
IV. 34 ATP molecules are produced via oxidative phosphorylation in ETS.

Which option contains all correct statements?

Consider the fate of glycolytic intermediates if drawn off for anabolic reactions:

I. Glucose-6-phosphate drawn off decreases total ATP yield.
II. DHAP drawn off for glycerol synthesis reduces pyruvate formation.
III. Net ATP yield remains 38 ATP even if all intermediates are withdrawn.
IV. Withdrawal of intermediates breaks theoretical sequential pathway assumptions.

Which statements are correct?

Balance sheet comparison for one molecule of Pyruvic acid entering aerobic respiration:

I. Link Reaction: 1 NADH = 3 ATP.
II. TCA Cycle: 3 NADH (9 ATP) + 1 FADH₂ (2 ATP) + 1 GTP (1 ATP) = 12 ATP.
III. Total ATP yield per Pyruvic acid = 15 ATP.
IV. Total CO₂ evolved per Pyruvic acid = 3 molecules.

Which statements are correct?

Consider the following statements regarding Amphibolic Pathway:

I. Respiration has traditionally been considered purely catabolic.
II. Respiratory intermediates serve as precursors for synthesis of fatty acids and proteins.
III. Acetyl-CoA may be withdrawn from the pathway for fatty acid synthesis.
IV. Because respiration participates in both catabolism and anabolism, it is called an amphibolic pathway.

Which statements are correct?

Points of entry of different respiratory substrates into the respiratory pathway:

I. Fats are broken into glycerol and fatty acids; glycerol enters as PGAL/DHAP.
II. Fatty acids are degraded to Acetyl-CoA before entering the TCA cycle.
III. Proteins are degraded into amino acids that enter as pyruvate, Acetyl-CoA or TCA intermediates.
IV. Carbohydrates must be converted to glucose before entering glycolysis.

Which option lists the correct entry points?

Definition and formula of Respiratory Quotient (RQ):

I. RQ = Volume of CO₂ evolved / Volume of O₂ consumed.
II. RQ depends on the type of respiratory substrate used.
III. RQ = Volume of O₂ consumed / Volume of CO₂ evolved.
IV. RQ is always equal to 1.0 for all organic substrates.

Which statements are correct?

Respiratory Quotient (RQ) values for different substrates:

I. Carbohydrates (e.g. glucose): RQ = 1.0.
II. Fats (e.g. tripalmitin): RQ = 0.7.
III. Proteins: RQ ≈ 0.9.
IV. Anaerobic respiration: RQ = ∞ because CO₂ is evolved without O₂ consumption.

Which option lists the correct RQ values?

Read the following statements regarding RQ calculation for Tripalmitin (C₅₁H₉₈O₆):

I. 2(C₅₁H₉₈O₆) + 145 O₂ → 102 CO₂ + 98 H₂O + energy.
II. Volume of CO₂ evolved = 102 molecules.
III. Volume of O₂ consumed = 145 molecules.
IV. RQ = 102/145 = 0.7.

Which statements are correct?