CBSE Class 11 Biology Respiration in Plants MCQs Set A

Practice CBSE Class 11 Biology Respiration in Plants MCQs Set A provided below. The MCQ Questions for Class 11 Chapter 12 Respiration in Plants Biology with answers and follow the latest CBSE/ NCERT and KVS patterns. Refer to more Chapter-wise MCQs for CBSE Class 11 Biology and also download more latest study material for all subjects

MCQ for Class 11 Biology Chapter 12 Respiration in Plants

Class 11 Biology students should review the 50 questions and answers to strengthen understanding of core concepts in Chapter 12 Respiration in Plants

Chapter 12 Respiration in Plants MCQ Questions Class 11 Biology with Answers

Question : What is the end product of glycolysis of a glucose molecule
a) Pyruvate and ATP
b) Phosphoglyceraldehyde
c) Lactic acid and ATP
d) Fructose 1, 6- diphosphate
Answer : A

Question : Connecting link between glycolysis and Krebs cycle is/ before entering Krebs cycle pyruvate is changed to
a) acetyl CoA
b) phosphoenol pyruvate
c) oxaloacetate
d) pyruvate
Answer : A

Question : Site of respiration in bacteria is
a) mesosome
b) episome
c) ribosome
d) microsome
Answer : A

Question : Which of the following processes make direct use of oxygen ?
a) Electron transport
b) Fermentation
c) citric acid cycle
d) None of these
Answer : A

Question : In Kreb’s cycle, the FAD participates as electron acceptor during the conversion of
a) succinic acid to fumaric acid
b) fumaric acid to malic acid
c) succinyl CoA to succinic acid
d) None of these
Answer : A

Question : The major reason that glycolysis is not as energy productive as respiration is that
a) pyruvate is more reduced than CO2; it still contains much of the energy from glucose
b) it does not take place in a specialized membrane-bound organelle.
c) it is the pathway common to fermentation and respiration
d) None of these
Answer : B

Question : Which of the following is a 4-carbon compound?
a) Oxaloacetic acid
b) Phosphoglyceric acid
c) Citric acid
d) Phosphoenol pyruvate
Answer : A

Question : Which of the following is a biological uncoupler of oxidative phosphorylation ?
a) Thermogenin
b) 2, 4 – Dichlorophenoxy acetic acid
c) 2, 4 – Dinitrophenol
d) Ethylene diaminotetra acetic acid
Answer : A

Question : Which of the following is not true for oxidative phosphorylation?
a) It uses oxygen as the initial electron donor.
b) It involves the redox reactions of electron transport chain
c) It involves an ATP synthase located in the inner mitochondrial membrane.
d) It depends on chemiosmosis
Answer : C

Question : Final electron acceptor in oxidative phosphorylation is
a) oxygen
b) hydrogen
c) cytochrome
d) None of these
Answer : oxygen

Question : Quantasomes are found in
a) chloroplast
b) mitochondria
c) lysosome
d) None of these
Answer : A

Question : Which of the following is an important intermediate found in all the types of respiration ?
a) Pyruvic acid
b) Tricarboxylic acid
c) Acetyl CoA
d) Oxaloacetate
Answer : A

Question : Incomplete oxidation of glucose into pyruvic acid with several intermediate steps is known as
a) Glycolysis
b) Krebs cycle
c) TCA-pathway
d) HMS-pathway
Answer : A

Question : Common enzyme in glycolysis and pentose phosphate pathways is
a) hexokinase
b) fumarase
c) aconitase
d) dehydrogenase
Answer : A

Question : One of the following is common to glycolysis as well as Krebs cycle in eukaryotes
a) Substrate level phosphorylation
b) Photophosphorylation
c) Localization in mitochondria
d) None of these
Answer : A

Question : A mutant cell lacking mitochondria will show
a) Inability to oxidize carbohydrates and fats
b) Inability to synthesize glucose
c) Inability to oxidize fats
d) Inability to oxidize carbohydrates
Answer : B

Question : During the early stages of alcoholic fermentation there is a high rate of growth of yeast. After some time the rate decreases. Which of the following conditions in the culture medium is least likely to have caused this?
a) Depletion of oxygen
b) Depletion of mineral salts
c) Accumulation of waste products
d) Depletion of glucose
Answer : A

Question : Hexose monophosphate shunt does not take place when
a) NAD is available
b) NAD is not available due to shortage of oxygen
c) Glucose is the substrate
d) Oxygen is not enough
Answer : A

Question : Chemiosmotic theory of ATP synthesis in the chloroplasts and mitochondria is based on
a) proton gradient
b) accumulation of Na ions
c) membrane potential
d) None of these
Answer : A

Question : The energy-releasing process in which the substrate is oxidised without an external electron acceptor is called
a) glycolysis
b) photorespiration
c) fermentation
d) aerobic respiration
Answer : A

 

Question : End product of glycolysis is 
a) acetyl Co-A
b) pyruvic acid
c) glucose 1-phosphate
d) fructose 1-phosphate
Answer : B
 
Question : EMP can produce a total of
a) 6 ATP
b) 8 ATP
c) 24 ATP
d) 38 ATP
Answer : B
 
Question : Connecting link between glycolysis and Krebs cycle is (before entering Krebs cycle pyruvate changed to)
a) oxaloacetate
b) PEP
c) pyruvate
d) acetyl Co-A
Answer : D
 
Question : Out of 36 ATP molecules produced per glucose molecule during respiration 
a) 2 are produced outside glycolysis and 34 during respiratory chain
b) 2 are produced outside mitochondria and 34 inside mitochondria
c) 2 during glycolysis and 34 during Krebs cycle
d) all are formed inside mitochondria
Answer : B
 
Question : End products of aerobic respiration are 
a) sugar and oxygen
b) water and energy
c) carbon dioxide, water and energy
d) carbon dioxide and energy
Answer : C
 
Question : Amino acids are mostly synthesized from 
a) mineral salts
b) fatty acids
c) volatile acids
d) α-ketoglutaric acid
Answer : D
 
Question : Apparatus to measure rate of respiration and RQ is 
a) auxanometer
b) potometer
c) respirometer
d) manometer
Answer : C
 
Question : When one glucose molecule is completely oxidised, it changes 
a) 36 ADP molecules into 36 ATP molecules
b) 38 ADP molecules into 38 ATP molecules
c) 30 ADP molecules into 30 ATP molecules
d) 32 ADP molecules into 32 ATP molecules
Answer : B
 
Question : Link between glycolysis, Krebs cycle and poxidation of fatty acid or carbohydrate and fat metabolism is 
a) oxaloacetic acid
b) succinic acid
c) citric acid
d) acetyl Co-A
Answer : D
 
Question : Oxidative phosphorylation is production of
a) ATP in photosynthesis
b) NADPH in photosynthesis
c) ATP in respiration
d) NADH in respiration

Answer : C

Question : Terminal cytochrome of respiratory chain which donates electrons to oxygen is
a) cyt. b
b) cyt. c
c) cyt. a1 
d) cyt.-a3
Answer : D
 
Question : At a temperature above 35°C 
a) rate of photosynthesis will decline earlier than that of respiration
b) rate of respiration will decline earlier than that of photosynthesis
c) there is no fixed pattern
d) both decline simultaneously
Answer : A
 
Question : Life without air would be 
a) reductional
b) free from oxidative damage
c) impossible
d) anaerobic
Answer : D
 
Question : Out of 38 ATP molecules produced per glucose,32 ATP molecules are formed from NADH/FADH2 in 
a) respiratory chain
b) Krebs cycle
c) oxidative decarboxylation
d) EMP
Answer : A
 
Question : End product of citric acid/Krebs cycle is
a) citric acid
b) lactic acid
c) pyruvic acid
d) CO2 + H2O
Answer : D
 
Question : In animal cells, the first stage of glucose break down is 
a) Krebs cycle
b) glycolysis
c) oxidative phosphorylation
d) ETC
Answer : B
 
Question : Respiratory substrate yielding maximum number of ATP molecule is 
a) ketogenic amino acids
b) glucose
c) amylose
d) glycogen
Answer : B
 
Question : ATP is injected in cyanide poisoning because it is 
a) necessary for cellular functions
b) necessary for Na+ –K+ pump
c) Na+–K+ pump operates at the cell membranes
d) ATP breaks down cyanide
Answer : A
 
Question : Fermentation products of yeast are
a) H2O + CO2
b) methyl alcohol + CO2
c) methyl alcohol + H2O
d) ethyl alcohol + CO2
Answer : D
 
Question : Which of the following is essential for conversion of pyruvic acid into acetyl Co-A?
a) LAA
b) NAD+
c) TPP
d) All of these
Answer : D
 
Question : Respiratory quotient (RQ) for fatty acid is
a) > 1
b) < 1
c) 1
d) 0
Answer : B
 
Question : Krebs cycle occurs in 
a) mitochondria
b) cytoplasm
c) chloroplast
d) ribosomes
Answer : A
 
Question : Oxidative phosphorylation involves simultaneous oxidation and phosphorylation to finally form 
a) pyruvate
b) NADP
c) DPN
d) ATP
Answer : D
 
Question : Fermentation is anaerobic production of
a) protein and acetic acid
b) alcohol, lactic acid or similar compounds
c) ethers and acetones
d) alcohol and lipoproteins
Answer : B
 
Question : The mechanism of ATP formation both in chloroplast and mitochondria is explained by
a) relay pump theory of Godlewski
b) Munch’s pressure/mass flow model
c) chemiosmotic theory of Mitchell
d) Cholondy-Went’s model
Answer : C
 
Question : In Krebs cycle FAD participates as electron acceptor during the conversion of 
a) succinyl Co-A to succinic acid
b) α-ketoglutarate to succinyl Co-A
c) succinic acid to fumaric acid
d) fumaric acid to malic acid
Answer : C
 
 
Question : Net gain of ATP molecules during aerobic respiration is 
a) 36 molecules
b) 38 molecules
c) 40 molecules
d) 48 molecules
Answer : B
 
 
Question : How many ATP molecules are produced by aerobic oxidation of one molecule of glucose?
a) 2
b) 4
c) 38
d) 34
Answer : C
 
 
Question : In which one of the following do the two names refer to one and the same thing?
a) Tricarboxylic acid cycle and urea cycle
b) Krebs cycle and Calvin cycle
c) Tricarboxylic acid cycle and citric acid cycle
d) Citric acid cycle and Calvin cycle
Answer : C
 
 
Question : In alcoholic fermentation
a) oxygen is the electron acceptor
b) triose phosphate is the electron donor while acetaldehyde is the electron acceptor
c) triose phosphate is the electron donor while pyruvic acid is the electron acceptor
d) there is no electron donor
Answer : B
 
 
Question : In glycolysis, during oxidation electrons are removed by 
a) ATP
b) glyceraldehyde-3-phosphate
c) NAD+
d) molecular oxygen
Answer : B
 
 
Question : During which stage, in the complete oxidation of glucose are the greatest number of ATP molecules formed from ADP 
a) glycolysis
b) Krebs cycle
c) conversion of pyruvic acid to acetyl Co-A
d) electron transport chain
d) electron transport chain
Answer : D
 
 
Question : Chemiosmotic theory of ATP synthesis in the chloroplast and mitochondria is based on
a) membrane potential
b) accumulation of Na+ions
c) accumulation of K+ ions
d) proton gradient
Answer : D
 
 
Question : How many ATP molecules could maximally be generated from one molecule of glucose, if the complete oxidation of one mole of glucose to CO2 and H2O yields 686 kcal and the useful chemical energy available in the high energy phosphate bond of one mole of ATP is 12 kcal? 
a) 30
b) 57
c) 1
d) 2
Answer : B
 
 
Question : The overall goal of glycolysis, Krebs cycle and the electron transport system is the formation of 
a) ATP in small stepwise units
b) ATP in one large oxidation reaction
c) sugars
d) nucleic acids
Answer : A

MCQs for Chapter 12 Respiration in Plants Biology Class 11

Students can use these MCQs for Chapter 12 Respiration in Plants to quickly test their knowledge of the chapter. These multiple-choice questions have been designed as per the latest syllabus for Class 11 Biology released by CBSE. Our expert teachers suggest that you should practice daily and solving these objective questions of Chapter 12 Respiration in Plants to understand the important concepts and better marks in your school tests.

Chapter 12 Respiration in Plants NCERT Based Objective Questions

Our expert teachers have designed these Biology MCQs based on the official NCERT book for Class 11. We have identified all questions from the most important topics that are always asked in exams. After solving these, please compare your choices with our provided answers. For better understanding of Chapter 12 Respiration in Plants, you should also refer to our NCERT solutions for Class 11 Biology created by our team.

Online Practice and Revision for Chapter 12 Respiration in Plants Biology

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