Grade 11 : Biology - Respiration in Plants (Set 4)

Question 1

Diagram layout showing Cell Cytoplasm surrounding a Mitochondrion.

In which part of the eukaryotic cell does glycolysis take place?

Accepted Answer

C) Cytoplasm / Cytosol

Answer

A) Mitochondrial matrix

Answer

B) Inner mitochondrial membrane

Answer

D) Peroxisome

Question 2

A student calculates the ATP yield during the initial cleavage and phosphorylation phases of glucose breakdown.

What is the net gain of ATP molecules produced directly via substrate-level phosphorylation during glycolysis of one molecule of glucose?

Accepted Answer

B) 2 ATP

Answer

A) 1 ATP

Answer

C) 4 ATP

Answer

D) 36 ATP

Question 3

Statement I: The Respiratory Quotient (RQ) depends upon the type of respiratory substrate used during respiration.
Statement II: When carbohydrates are used as substrate and are completely oxidized, the RQ is equal to 1.

Select the correct option regarding Statement I and Statement II.

Accepted Answer

A) Both Statement I and Statement II are correct

Answer

B) Both Statement I and Statement II are incorrect

Answer

C) Statement I is correct but Statement II is incorrect

Answer

D) Statement I is incorrect but Statement II is correct

Question 4

[ETS Chain] Complex I → Complex III → Complex IV → [Final Acceptor]

Which molecule acts as the terminal electron acceptor in the mitochondrial electron transport system (ETS)?

Accepted Answer

C) Oxygen (O2)

Answer

A) Cytochrome c

Answer

B) NAD+

Answer

D) Water (H2O)

Question 5

Complex IV of the inner mitochondrial membrane respiratory chain is also known as which enzyme complex?

Accepted Answer

D) Cytochrome c oxidase

Answer

A) NADH dehydrogenase

Answer

B) Succinate dehydrogenase

Answer

C) Cytochrome bc1 complex

Question 6

Pyruvate generated in the cytoplasm enters the mitochondrial matrix for oxidative decarboxylation before entering the TCA cycle.

Which enzyme complex catalyzes the conversion of pyruvate to acetyl CoA in the mitochondrial matrix?

Accepted Answer

B) Pyruvate dehydrogenase

Answer

A) Pyruvate kinase

Answer

C) Isocitrate dehydrogenase

Answer

D) Malate dehydrogenase

Question 7

What are the main end products of alcoholic fermentation in yeast cells under anaerobic conditions?

Accepted Answer

B) Ethanol, CO2, and ATP

Answer

A) Lactic acid and ATP

Answer

C) Pyruvate and H2O

Answer

D) Acetyl CoA and CO2

Question 8

Where does the Tricarboxylic Acid (TCA) cycle / Krebs cycle take place inside a eukaryotic cell?

Accepted Answer

C) Mitochondrial matrix

Answer

A) Cytosol

Answer

B) Outer mitochondrial membrane

Answer

D) Thylakoid lumen

Question 9

Substrate	Respiratory Quotient (RQ)
Carbohydrate	1.0
Fats / Lipids	0.7
Proteins	0.9
Organic Acids	> 1.0

Based on the provided table, which substrate requires more oxygen relative to the volume of CO2 evolved during its complete oxidation?

Accepted Answer

B) Fats

Answer

A) Carbohydrates

Answer

C) Organic acids

Answer

D) Glucose

Question 10

How many carbon dioxide (CO2) molecules are released per turn of the TCA cycle (starting from Acetyl CoA)?

Accepted Answer

B) 2

Answer

A) 1

Answer

C) 3

Answer

D) 4

Question 11

Pathway step: Phosphoenolpyruvate (PEP) + ADP → Pyruvate + ATP (Catalyzed by Enzyme X)

Identify Enzyme X that catalyzes the final ATP-generating step of glycolysis.

Accepted Answer

C) Pyruvate kinase

Answer

A) Hexokinase

Answer

B) Phosphofructokinase

Answer

D) Enolase

Question 12

Which 4-carbon compound acts as the primary acceptor of acetyl CoA (2C) to initiate the TCA cycle?

Accepted Answer

B) Oxaloacetic acid (OAA)

Answer

A) Citrate

Answer

C) Succinate

Answer

D) Malate

Question 13

During an experiment using a respirometer, 102 molecules of CO2 are evolved while 145 molecules of O2 are consumed during the oxidation of tripalmitin.

Calculate the approximate Respiratory Quotient (RQ) for tripalmitin.

Accepted Answer

B) 0.7

Answer

A) 1.0

Answer

C) 1.4

Answer

D) 0.9

Question 14

[ATP Synthase (Complex V)] = F0 (Transmembrane channel) + F1 (Headpiece in matrix)

Which component of ATP Synthase (Complex V) acts as a peripheral membrane protein complex containing the catalytic site for ATP synthesis?

Accepted Answer

B) F1 headpiece

Answer

A) F0 part

Answer

C) Cytochrome c

Answer

D) Ubiquinone

Question 15

At which specific step in the TCA cycle does direct substrate-level phosphorylation occur, generating GTP or ATP?

Accepted Answer

C) Succinyl-CoA to Succinic acid

Answer

A) Citrate to Isocitrate

Answer

B) Alpha-Ketoglutarate to Succinyl-CoA

Answer

D) Fumarate to Malate

Question 16

During anaerobic respiration in human skeletal muscles during strenuous exercise, pyruvate is reduced to which 3-carbon compound?

Accepted Answer

B) Lactic acid

Answer

A) Ethanol

Answer

C) Acetaldehyde

Answer

D) Oxaloacetate

Question 17

Complex III (Cytochrome bc1) → [ Mobile Carrier Cyt c ] → Complex IV (Cytochrome c oxidase)

What is the key role of Cytochrome c in the electron transport chain?

Accepted Answer

B) Mobile electron carrier between Complex III and Complex IV

Answer

A) Fixed integral enzyme in Complex I

Answer

C) Primary enzyme synthesizing ATP directly

Answer

D) Proton pump moving protons into matrix

Question 18

How many molecules of NADH + H+ are produced per molecule of acetyl-CoA oxidized in one turn of the TCA cycle?

Accepted Answer

C) 3

Answer

A) 1

Answer

B) 2

Answer

D) 4

Question 19

Statement I: The respiratory pathway involves both breakdown (catabolism) of substrates and synthesis (anabolism) of respiratory intermediates.
Statement II: Because the respiratory pathway is involved in both catabolism and anabolism, it is correctly termed an amphibolic pathway.

Which of the following options correctly evaluates Statements I and II?

Accepted Answer

A) Both Statement I and Statement II are correct

Answer

B) Statement I is correct but Statement II is incorrect

Answer

C) Statement I is incorrect but Statement II is correct

Answer

D) Both Statement I and Statement II are incorrect

Question 20

Substrate	Respiratory Quotient (RQ)
Carbohydrate	1.0
Fats / Lipids	0.7
Proteins	0.9
Organic Acids	> 1.0

Based on cellular localization and pathway traits, which of the following is common to BOTH Glycolysis and Krebs Cycle?

Accepted Answer

B) Both generate NADH reduced coenzymes

Answer

A) Both occur in the mitochondrial matrix

Answer

C) Both directly require molecular oxygen (O2) as a reactant

Answer

D) Both produce carbon dioxide (CO2) molecules

Grade 11 : Biology - Respiration in Plants (Set 4)