1

RESPIRATION IN PLANTS

1 INTRODUCTION

All living organisms need energy for

carrying out daily life activities, be it

absorption, transport, movement,

reproduction or even breathing.

All the energy required for ‘life’

processes is obtained by oxidation of

some macromolecules that we call

‘food’. Only green plants and

cyanobacteria can prepare their own

food; by the process of

photosynthesis

Photosynthesis, of course, takes

place within the chloroplasts (in the

eukaryotes), whereas the breakdown

of complex molecules to yield energy

takes place in the cytoplasm and in

the mitochondria (also only in

eukaryotes).

The breaking of the C-C bonds of

complex compounds through

oxidation within the cells, leading to

release of considerable amount of

energy is called respiration. The

compounds that are oxidized during

this process are known as respiratory

substrates. Usually carbohydrates are

oxidised to release energy, but

proteins, fats and even organic acids

can be used as respiratory

substances in some plants, under

certain conditions.

During oxidation within a cell, all the

energy contained in respiratory

substrates is not released free into

the cell, or in a single step. It is

released in a series of slow step-wise

reactions controlled by enzymes, and

it is trapped as chemical energy in

the form of ATP.

2 HOW DO PLANTS BREATHE?

First, each plant part takes care of its

own gas-exchange needs. There is

very little transport of gases from

one plant part to another.

Second, plants do not present great

demands for gas exchange. Roots,

stems and leaves respire at rates far

lower than animals do. Only during

photosynthesis are large volumes of

gases exchanged and, each leaf is

well adapted to take care of its own

needs during these periods. When

cells photosynthesize, availability of

O2 is not a problem in these cells

since O2 is released within the cell.

Third, the distance that gases must

diffuse even in large, bulky plants is

not great. Each living cell in a plant is

located quite close to the surface of

the plant. In stems, the ‘living’ cells

are organised in thin layers inside

and beneath the bark. They also have

openings called lenticels. The cells in

the interior are dead and provide only

mechanical support. Thus, most cells

of a plant have at least a part of their

surface in contact with air. This is

also facilitated by the loose packing

of parenchyma cells in leaves, stems

and roots, which provide

interconnected network of air spaces.

3. RESPIRATION CELLULAR

Respiration is aAmphibolic&exergonic

cellular process. Respiration is an

enzymatic process.

An important feature of respiration is

liberation metabolic energy as ATP.

3.1 TYPES OF RESPIRATION

(A) Aerobic respiration: The complete

oxidation of food with the use of

oxygen and when entire carbon

released, CO2 is called as aerobic

respiration. enzyme

6 12 6 2 2 2Cytoplasm&

Mitochondrfa

C H O 6O 6CO 6H O 686K.cals / 2867kJ.

(Glucose)

(B) Anaerobic Respiration :This is an incomplete oxidation.

When food is oxidized into alcohol or

organic acids without use of oxygen.

During it most of the energy is lost in

form of heat. It occurs in cytoplasm

and only 2ATP are produced.

2

Enzyme

6 12 6 2 5 2CytoplasmC H O 2C H OH 2CO 50K.cal / 210kJ

(2ATP)

The amount of energy released in

anaerobic respiration is much less

than aerobic respiration.

DIFFERENCES BETWEEN RESPIRATION AND

COMBUSTION

S.No Respiration Combustion

1 It is a

biochemical

process

It is a

physicochemical

process

2 It occurs under

biological

control

It does not

occurs under

biological

control

3 Only a part of

energy is lost as

heat

Almost entire

energy is

released as heat

4 Temperature

remains low

Temperature

rises

considerably

5 Most of the

energy is

entrapped in the

phosphate

bonds of ATP

No ATP is

formed

6 Each step of

respiration is

catalyzed by an

enzyme

No enzyme is

involved.

3.2 STEPS OF AEROBIC RESPIRATION

1. Glycolysis – Occurs in cytosol /

cytoplasm

2. Formation of Acetyl COA (Link

Reaction) - mitochondrial matrix

3. TCA cycle or Kreb’s cycle -

mitochondrial matrix

4. ETC(Electron transport Chain) Inner

membrane of mitochondria or cristae

and Oxidative phosphorylation -

occurs in oxysome head (F1 particle)

3.2.1 GLYCOLYSISE EMPATHWAY

In plants glucose is derived from sucrose. sucrose is converted into glucose & fructose by Invertase enzyme.

It is a partial oxidative process in

which Hexose (Glucose or fructose)

splits to form two molecules of

pyruvic acid. It is also called EMP

pathway because it was discovered

by three German scientistsEmbden,

Meyerhofand Parnas (EMP).

1, 3, 10 are irreversible reactions in

glycolysis. ENERGY PRODUCTION IN GLYCOLYSIS

In glycolysis one molecule of hexose sugar is splitted to form two molecules of 3-C compound pyruvic acid. 4 molecules of ATP are

GLUCOSE

GLUCOSE-6-PHOSPHATE

FRUCTOSE-6-PHOSPHATE

ATPMg

++

ADPHexokinase

Phosphohexoisomerase

ATPMg

++

ADP

FRUCTOSE-1.6-DIPHOSPHATE

Aldolase

3-PHOSPHOGLYCERALDEHYDE

2H PO3 4

Isomerase

DIHYDROXY ACETONEPHOSPHATE

Phosphofructokinase

1,3-DIPHOSPHOGLYCERALDEHYDE

1,3-DIPHOSPHOGLYCERIC ACID

2 NAD+

2NADH.H+Dehydrogenase

3-PHOSPHOGLYCERIC ACID

2ADP

2ATPPhosphoglycerate kinase

2-PHOSPHOGLYCERIC ACID

Phosphoglycerate mutase

PHOSPHOENOL PYRUVATE

Enolase2H O2

PYRUVIC ACID

2 ADP

2ATP

Pyruvic kinase

Mg , K++ +

2 mol.

2 mol.

2 mol.

2 mol.

2 mol.

2 mol.

to ETS

Fig : Different steps of Glycolysis

Mg++

3

produced and 2 molecules of ATP are consumed so net gain is 2 ATP.

Molecules of NADH.H+ are also

produced which enter into

mitochondria and are oxidized

through ETS to form 6 ATP. So

glycolysis in aerobic condition can

produce 2 + 6 = 8 ATP.

EAGEL EYE

Substrate level phosphorylation form

4 ATP – When the substrate releases

energy for phosphorylation of ADP OR

formation of ATP, without ETS then

called as substrate

levelphosphorylation.

3.2.2 OXIDATIVE DECARBOXYLATION OF PYRUVIC ACID OR LINKING REACTION BETWEEN GLYCOLYSIS & KREB’S CYCLE

The pyruvic acid (3C) undergoes

oxidative decarboxylation and forms

acetyl Co-A (2C). It takes place in

mitochondria.

This reaction is catalysed by enzyme

pyruvate dehydrogenase and five co-

factors TPP (thiamine

pyrophosphate), Co-A, Lipoic acid,

FMN, NAD and Mg++ ions.

,

Pyruvatedehydrogena se

Mg ,TPP,Lipoic acidPyruvicacid Co A NAD

2AcetylCo A CO NADH H

3.2.3 KREBS’ CYCLE Or TRICARBOXYLIC ACID

CYCLE Or CITRIC ACID CYCLE Or

AMPHIBOLIC PATHWAY

It was discovered by Hans Krebs in

muscles of pigeon.

TCA cycle occurs in mitochondrial

matrix.

It is also called Tricarboxylic acid

cycle (TCA cycle) or citric acid

cycle(CACcycle) because its first

stable product citric acid contains

three carboxylic groups (–COOH).

Krebs’ cycle begins by formation of

citric acid [TCA (Tri carboxylic acid)]

&O.A.A. is the first member of Krebs’

cycle.

A number of Krebs’ cycle

intermediates are used in synthetic

(anabolic) pathways, thus TCA cycle

is also called amphibolic pathway or

anaplerotic pathway.

Oxidation occurs at 4 sites in Krebs’

cycle.

One molecule of Acetyl Co-A yields 3

NADH.H+, 1 FADH.H+ and 1 GTP (=12

ATP) through one Krebs’ cycle.

Thus one molecule of pyruvic acid

yields 4 NADH.H+, 1 FADH.H+, and one

ATP molecule ( = 15 ATP) so two

molecules of pyruvic acid will

produce 30 ATP. Similarly one

molecule of pyruvic acid on oxidation

4

through Krebs’ cycle yields 3

molecules of CO2. Thus two

molecules of pyruvic acid will

produce 6 molecules of CO2.

EAGEL EYE

All the enzymes of TCA cycle, except

marker enzyme Succinic

dehydrogenase (on inner

mitochondrial membrane or Cristal)

present in matrix.

Actually NADH2& FADH2form ATP

through ETS.

Malonate is competitive inhibitor

succinic of dehydrogenase.

Example-1

Q1. The pyruvic acid formed in glycolysis

is oxidized to CO2 and H2O in a cycle

called

(A) Calvin cycle

(B) Hillreaction

(C) Krebs’ cycle

(D) Nitrogen cycle

Sol. (A) In Aerobic Respiration, glucose is

completely oxidized into CO2& H2O

and Krebs’ cycle or TCA Cycle is part

of Aerobic Respiration.

Q2. Before combining with OAA, pyruvic

acid is changed into

(A) Succinic acid

(B) Malic acid

(C) Acetyl Co-A

(D) Citric acid

Sol. (C) Pyruvic acid (3C) undergoes

oxidative decarboxylation to form

AcetylCoA(2C).

Booster -1

Q1. Two names referring to same thing

(A) Krebs’ cycle and Calvin cycle

(B) Tricarboxylic acid cycle and citric

acid cycle

(C) Citric acid cycle and Calvin cycle

(D) Tricarboxlic acid and urea cycle.

Ans. (B)

Q2. Enzyme of TCA which is located in

inner mitochondrial membrane in

eukaryotes and cytosol in prokaryotes

is

(A) Lactate dehydrogenase

(B) Malate dehydrogenase

(C) Isocitrate dehydrogenase

(D) Succinate dehydrogenase.

Ans. (D)

3.2.4 TERMINAL OXIDATION OF NADH2&

FADH2

Atmospheric O2 is directly involved in

the end of catabolic process.It includes two steps.

(A)Electron transport system or ETS (B) Oxidative Phosphorylation

(A) Electron transport system or ETS

It occurs in F1 particles or oxysomes

which are located on the inner

membrane of mitochondria.

In each group the enzymes are

arranged in a specific series called

electron transport chain (ETC) or

mitochondrial respiratory chain or

electron transport system (ETS).

Inner mitochondrial membrane

possesses five complexes.

S.No Name of

complexes

Parts of ETS

1. Complex –I FMN-NADH2

Dehydrogenase

2. Complex –II CoQ/UQ-FADH2

Dehydrogenase

/Succinate

dehydrogenase

3. Complex –III Cyt. b-cyt c

4. Complex –IV Cyt. a & Cyt.a3 (Cu

Present )

5. Complex –V ATP

synthase/ATPase

Complexes-I to IV are involved in electron

transport whereas Complex V (F0–F1

particle) is connected with ATP synthesis.

It includes following steps

(i) ETS consists of Flavins, FeS

complexes, Quinone and

cytochromes. Quinone is ubiquinone

or CoQ. Electrons enter the

5

mitochondrial electron transport

chain at two routes-at FMN and at

FAD. These routes join at Coenzyme

Q, where the electrons coming from

the two routes collect.

(ii) NADH transfer its electron and H+

ions to FMN, the

(iii) H-ions move to the outer chamber of

mitochondria while electrons are

accepted by cytochromes.

1 3Cyt b Cyt C Cyt C Cyt a Cyta Cytochrome a & a3 are collectively called

cytochrome oxidase. While Cytochrome a3 is

called terminal oxidase.

(iv) In cytochrome, iron functions as

activator. It accept (Fe+++ + e-= Fe++)

and donate (Fe++e-= Fe+++) electrons.

(v) These electrons from cytochrome

oxidase react with atom of oxygen

making it active. This activated

oxygen reacts with 2 Hydrogen ions

forming moleculeof water. +2H- -2

21O+2e O H O

2

(B) Oxidative Phosphorylation : Synthesis of ATP in the presence of

oxygen in mitochondria is called

Oxidative Phosphorylation. The latter

can be explained by Chemiosmotic

theory.

CHEMIOSMOTIC THEORY

It was proposed by Peter Mitchell (1961).He got NobelPrize in 1978.

During oxidation of NADH the H+ ions move in outer chamber of mitochondria that causes different pH across the membrane which creates an electric potential across the inner mitochondrial membrane that produces proton gradient or proton motive force.

Proton motive force causes the flow of protons from the outer chamber across the inner mitochondrial membrane in to matrix. Protons pass through the Fo - F1 ATPase

particlewhere ATPase catalyses the synthesis of ATP from ADP + Pi.

Route 1 of ETS - 3ATP are synthesized by the complete

oxidation of 1 molecule of NADH.H+. Route 2 of ETS - Only 2 ATP are

synthesized by complete oxidation of

one mole of FADH.H+.

3.2.5 THE RESPIRATORY BALANCESHEET

6

Stage Productio

n of ATP

by

substrate

level

phosphory

lation

Formati

on of

NADH/F

ADH

Synthesi

s of ATP

by ETS

in

Mitocho

ndria

Glycolysis 2 2 NADH 2 3 =

6

Oxidative

decarboxy

lation of

Pyruvic

acid

2 NADH 2 3 =

6

Krebs’

Cycle

2 6 NADH 6 3 =

18

2 2 =

4

4 2 FADH 34 (or

32)

3.2.6 BIOENERGETICS OF RESPIRATION (1

MOL. OF GLUCOSE)

(1) EMP-Pathway

(i) ATP formed at substrate level

Phosphorylation 4 ATP

(ii) ATP produced via ETS (2NADH2) 6 ATP

(iii) ATP consumed in glycolysis 2 ATP

10 ATP – 2 ATP =

Gross – Expenditure = Net or Total gain

Direct Gain = 2 ATP

(2) Link reaction or Gateway reaction –

2NADH2 = (via ETS)

(3) Krebs’ Cycle –

(i) ATP produced at substrate level phosphorylation = 2 GTP/2ATP

(ii) ATP produced via ETS

6NADH2 18 ATP

2FADH2 4 ATP

Total

Thus complete oxidation of one

molecule of glucose produces 38 ATP

(or 36 ATP). The production of 38 ATP

or 36 ATP in respiration depends

upon types of shuttle system either

malate aspartate shuttle or glycerol

phosphate shuttle.

EAGEL EYE

1 Pyruvic acid = 15 ATP

1 Acetyl Co-A or TCA cycle = 12 ATP

4. ANAEROBIC RESPIRATION It does not use molecular oxygen and

incompletely oxidizes the organic food with or without production of CO2. It therefore releases a small

amount of energy. It is also called intra-molecularrespiration.

Enzyme6 12 6 2 5 2C H O 2C H OH + 2CO +50K.cal/210kJ

(Glucose) (Ethyl alcohol)

The organisms which carry on

anaerobic respiration are termed

anaerobes.

4.1 FERMENTATION

Fermentation is much similar to

anaerobic respiration, but this is an

extracellular process & substrate is

present outside the cell. Energy

released as heat, no ATP generated.

Types of Fermentation

When the one type of product is

formed in fermentation then it is

called homofermentation.

When the products of fermentation

process are more than one type, then

process is heterofermentation.

6ATP

8 ATP

24 ATP

38 ATP

7

1. Alcoholic fermentation : This process

starts through the formation of

pyruvic acid from glucose. Alcohol is

formed by pyruvic acid in two steps.

decarboxylase3 3 2

TPP2CH .CO.COOH 2 CH CHO + 2CO

(Pyruvic acid) (Acetaldehyde)

+ decarboxylase3 2 52CH . CHO + 2NADH. H 2C H OH 2NAD

(Pyruvicacid) (Ethyl alcohol)

EAGEL EYE

Yeasts poison themselves to death

when the concentration of alcohol

reaches about 13 per cent.

Difference between Aerobic and Anaerobic

respiration

S.No. Aerobic respiration Anaerobic

respiration

1. It uses O2 It does not

use O2

2. CO2 and H2O

produce due to

destruction of

glucose

Glucose

reduces into

CO2 and

alcohol

3. It occurs in majority

of organisms

(animal & plants)

It occurs in

few organism

(yeasts, some

bacteria and

parasitic

form)

4. It occurs in

cytoplasm &

mitochondria

It occurs in

cytoplasm

only

5. Its 50% chemical

energy convert into

kinetic energy

Less than

10% chemical

energy of its,

convert into

kinetic

energy

6. 38 ATP produce Only 2 ATP

produce

7. It involves 5 steps

Glycolysis, pyruvate

oxidation, TCA

cycle, ETS and

chemiosmotic ATP

synthesis

It involves 2

steps –

Glycolysis

and

incomplete

breakdown of

pyruvate

8. It enzymes present

in both cytoplasm

and mitochondria

It enzymes

present only

in cytoplasm

Examples -2

Q1. Energy release in both respiration and burning of coal but respiration is a systematic process due to

(A) Control through enzymes (B) Control through hormone (C) Combustion

(D) Respiratory substance.

Sol. (A) During oxidation within a cell, all

the energy contained in respiratory

Substrates are not released in a

single step. It is released in series of

slow step-wise reaction controlled by

enzymes.

Q2. Net gain of ATP molecules per hexose

during aerobic respiration is

(A) 12

(B) 18

(C) 30

(D) 36

Sol. (D) In Aerobic respiration 36 ATP

formed.

Booster-2

Q1. Link enzyme in cellular respiration is (A) Citrate synthetase (B) Pyruvate dehydrogenase (C) Isocitrate dehydrogenase

8

(D) Succinylthiokinase

Ans. (B)

Q2. Terminal acceptor of electrons in ETC is

(A) H2O

(B) Cytochrome

(C) O2

(D) Flavoprotein

Ans. (C)

6. RESPIRATORY QUOTIENT OR R.Q.

R.Q. is the ratio of the volume of CO2

released to volume of oxygen taken in respiration.

2 2

2 2

Volume of CO released COR Q = =

Volume of O Consumed O

RQ is determined by respirometer. Rate of respiration is measured by Ganong'srespirometer.

1. R.Q. of carbohydrates When carbohydrates are the

respiratory substrate than R.Q. is one

6 12 2 2 2C H + 6O + 6CO + 6H O +686 K.cals.

2

2

6 6. 1

6 6

CORQ

O

2. R.Q. of Fats : When fats are the respiratory substrate, the value of R.Q. become less than one because the fats are poorer in oxygen and they require more O2for their oxidation.

51 98 6 2 2 2

2

2

2C H O +145O 102CO +98H O + E

(Tripalmatin)

102CO 102R.Q = = =0.70

145O 145

R.Q. of Proteins : When proteins are the respiratory

substrate, the value of R.Q. become less than one (usually 0.9).

2. R.Q. of organic acid :

When organic acid (in succulent

plants in presence of light) are

oxidized in respiration the R.Q.

become more than one because

organic acids are rich in O2 and

requires less O2 for their oxidation.

2 2 2 2

2

2

2(COOH) O 4CO + 3H O + E

(Oxalic acid )

4CO 4R.Q = = =4

O 1

4 6 5 2 2 2

2

2

C H O +3O 4CO +3H O + E

(Malic acid )

4CO 4R.Q = = =1.33

3O 3

5. R.Q. in succulent plants : In some fleshy or succulent plants

e.g. Opuntia, Bryophyllum.

Carbohydrates are incompletely

oxidized to organic acid in dark

without the evolution of CO2 thus

the value of R.Q. remain 0.

6 12 6 2 2 6 5 2

2

2

2C H O 3 3C H O +3H O + E

(Glucose) (Malic acid)

CO 0R.Q = = = 0

3O 3

O

6. R.Q. of matured fatty seeds : In matured fatty seeds,

carbohydrates are converted in to fats resulting O2 liberates which get

consumed in respiration and CO2

formed. Thus R.Q. of these seeds is more than one because they take less O2 from environment for

oxidation. Due to above reaction during maturing of fruits, the R.Q. of letter is also more than one.

7. R.Q. during anaerobic respiration:

Due to absence of O2 the value of

R.Q. is infinite because CO2 evolved

without the intake of oxygen.

6 12 6 2 6 2

2

2

C H O + 2C H OH + 2CO + E

(Glucose)

2CO 2R.Q = = = (Infinite)

O 0

EAGEL EYE

When respiratory substrates are

carbohydrates like glycogen, starch,

sucrose, hexose or fats, then

respiration is known as floating

respiration.

9

When protein is oxidised in

respiration, then respiration is known

as protoplasmic respiration

protoplasmic components or cellular

proteins may oxidised at the time of

starvation & disease.

Exchange of respiratory gases (O2

and CO2) between an organism and

its environment is called external respiration.

Exchange of respiratory gases between tissue cells and extracellular environment is called internal respiration.

1 molecule of glucose yields 56 Kcal

or 2 ATP in anaerobic respiration and

686000 calories (686kcal) or total of

38 ATP in aerobic respiration but net

gain of ATP in eukaryotes is 38 or 36

depending upon type of shuttle

system. Thus ratio of ATP in aerobic

and anaerobic respiration is 36:2 i.e.,

18:1 or 38:2 i e., 19:1.

Climacteric respiration is sudden increase in respiration during the ripening of some fleshy fruits like Apple.

Extinction point: It is the minimum concentration of oxygen below which aerobic respiration is stopped.

Photosynthesis is 10 times faster than respiration.

PGAL is connecting link between respiration and photosynthesis.

RBC and muscles obtain energy by glycolysis or anerobic respiration.

-ketoglutaric acid is only 5C compound of Krebs’ cycle. It functions as a connecting link between respiration and protein synthesis. It is a key substance in nitrogen metabolism.

Krebs’ cycle is amphibolic cycle. It undergoes2 decarboxylation and 4

oxidation to form CO2& H

2O.

Pasteur effect : Reduction in consumption of respiratory

substrate when the mode of respiration is changed from anaerobic to aerobic.

ETS poison : (i) 2, 4-dinitrophenol: It allows electron

transport but inhibits ATP formation from ADP

(ii) Antimycin A: It prevents electron transport between Cyt. b and Cyt. c

1

(iii) Cyanide: It inhibits transfer of electrons from Cyt. a3 to oxygen

(iv) Rotenone: It checks flow of electrons from Fes to CoQ.

In Mitochondria of some plants,

Alternative oxidase is found & ETS

continuously proceeds even in the

presence of cyanide. It is called

cyanide Resistant Respiration (CRR) or

Alternate electron pathway Ex:

Spinach.

Example-3

Q1. R.Q. of anaerobic respiration is (A) Zero (B)

(C) 1

(D) > 1.

Ans. (B)

Sol. (B) Due to absence of O2 the value of

R.Q. is infinite because CO2 evolved

without the intake of oxygen.

6 12 6 2 6 2C H O + 2C H OH +2CO +E

(Glucose)

2

2

2 CO 2R.Q.

O 0

Q2. Which is product of oxidative pentose

phosphate pathway?

(A) Pyruvic acid (B) Acetyl CoA

(C) NADH2

(D) NAD (P) H

Sol. (D) Pentose phosphate pathway of

respiration occur in cytoplasm of cell

and aim of PPP is NADPH.

Booster-3

Q1. Number of glucose molecule required to produces 38 ATP molecules under anaerobic conditions is

(A) 2 (B) 4

(C) 19

(D) 38.

Ans. (C)

Q2. Pasteur effect is (A) Storage of fermentation in

presence of oxygen (B) Increase of fermentation in

presence of oxygen

10

(C) Decrease in fermentation in presence of oxygen

(D) No effect on fermentation

Ans. (A)

Cellular Respiration

Exercise - 1

Introduction

Q1. Respiration may take place – (A) In the presence of O2 (B) In the absence of O2 (C) In the presence or absence of O2 (D) In the presence of CO2

Q2. Respiration occurs in (A) All living cells both in light& dark (B) Non green cells only in light (C) Non green cells in both light and

dark (D) All living cells in light only

Q3. Common immediate source of energy in cellular activity is (A) glucose (B) aldohexose (C) ATP (D) NAD

Q4. End products of respiration in plants are (A) CO2, H2O and energy (B) Starch and O2 (C) Sugar and oxygen (D) H2O and energy

Q5. Energy obtained by a cell from catabolic reaction is stored immediately in the form of (A) Pyruvic acid (B) Glucose (C) ATP (D) DNA

Q6. Exchange of respiratory gases between an organism and its environment is called (A) Respiration (B) External respiration (C) Internal respiration (D) Cellular respiration

Q7. CO2 is liberated during

(A) Ascent of sap (B) Transpiration (C) Photosynthesis (D) Respiration.

Q8. The overall goal of glycolysis, Krebs’ cycle and the electron transport system is the formation of (A) ATP is one large oxidation reaction (B) Sugars (C) Nucleic acid (D) ATP in small stepwise units.

Glycolysis Q9. In glycolysis, during oxidation electrons

are removed by : (A) Molecular oxygen (B) ATP (C) Glyceraldehyde (D) NAD+

Q10. The enzyme which converts glucose to glucose-6-phosphate - (A) Phosphorylase (B) Gluco-phosphorylase (C) Hexokinase (D) Phosphoglucomutase

Q11. Glycolysis give rise to (A) 8ATP, 2NADH(H+), 2 Pyruvate (B) 2 ATP, 2CoA, 2NADH(H+) (C) 2 ATP, 2NADH(H+) ,2 Pyruvate (D) 2 ATP, 2 acetate, 2NADH(H+)

Q12. Enzyme aldolase splits fructose-1,6-bisphosphate into (A) 2 molecules of PGA (B) 2 molecules of glyceraldehyde 3-

phosphate (C) A molecule each of glyceraldehyde

3-phosphate and dihydroxy acetone 3-phosphate

(D) Two molecules of DHAP. Q13. Phosphorylation of glucose during

glycolysis is catalysed by (A) Phosphoglucomutase (B) Phosphoglucoisomerase (C) Hexokinase (D) Phosphorylase

Q14. Which one of the following is the first step of glycolysis? (A) Breakdown of glucose (B) Conversion of glucose into fructose (C) Phosphorylation of glucose (D) Dehydrogenation of glucose.

Q15. The intermediate compound common for aerobic and anaerobic respiration is (A) Citric acid (B) Pyruvic acid (C) Acetyl CoA (D) Succinic acid

Q16. Which of the following is an important intermediate found in all the types of respiration? (A) Acetyl CoA

12

(B) Pyruvic acid (C) Oxaloacetate (D) Tricarboxylic acid

Q17. In glycolysis, the end product is (A) Phosphoglyceric acid (B) Citric acid (C) Pyruvic acid (D) Glucose.

Q18. During glycolysis, how many molecules of ATP is utilised to change glucose into fructose 1, 6-diphosphate? (A) 4 (B) 3 (C) 2 (D) 1

Q19. Which of the following is incorrect for glycolysis? (A) The end products of this process are

CO2 and H

2O

(B) It produces ATP (C) It uses ATP (D) None of these.

Q20. The net gain of ATP during glycolysis is (A) Two (B) Four (C) Six (D) Eight.

Q21. NAD is (A) Nicotinamide adenosine diphosphate (B) Nicotine adenosine phosphate (C) Nicotinamide adenine dinucleotide (D) None of these.

Q22. Glycolysis occurs in (A) Nucleus (B) Cytoplasm (C) Mitochondria (D) Lysosome.

Q23. In glycolysis, enzyme playing key role in splitting 6C compound into 3C compounds is (A) Hexokinase (B) Aldolase (C) Isomerase (D) None of these.

Q24. The common phase between aerobic and anaerobic respiration is (A) Krebs’ cycle (B) TCA cycle (C) EMP pathway (D) Oxidative phosphorylation.

Q25. In glycolysis, 3-phosphoglyceraldehyde is oxidised to form (A) Phosphoenol pyruvate (B) 2-phosphoglycerate (C) 3-phosphoglycerate (D) 1, 3-biphosphoglycerate.

Q26. Glyceraldehyde phosphate is oxidized during glycolysis. What is the fate of hydrogen atom and electron liberated? (A) They bring about oxidation of NAD

(B) They are transferred to oxaloacetic acid

(C) They are eliminated to form methane

(D) They reduce NAD+. Q27. Conversion of phosphenol pyruvic acid

to pyruvic acid and ADP to ATP are examples of (A) Photophosphorylation (B) Oxidative phosphorylation (C) Photoelectric phosphorylation (D) Substrate level phosphorylation

Q28. The energy-releasing metabolic process in which substrate is oxidised without an external electron acceptor is called (A) Fermentation (B) Aerobic respiration (C) Photorespiration (D) Glycolysis.

Q29. Which group of scientists from the following discovered glycolytic pathways of glucose degradation? (A) Embden, Morrison and Pitches (B) Emerson, Hoffman and Paterson (C) Embden, Myerhof and Parnas (D) Avery, Mcleod and McCarthy.

Q30. In glycolytic pathway, which of the following steps shows reduction of coenzyme (A) 1, 3-diphosphoglycerate to 3-

phosphoglycerate (B) Glucose 6-phosphate to fructose 6-

phosphate (C) 3-phosphoglycerate to 2-

phosphoglycerate (D) Glyceraldehyde 3-phosphate to 1,3-

diphosphoglycerate. Q31. Net gain of ATP from one molecule of

glucose in glycolysis is (A) 2 (B) 3 (C) 6 (D) 8

Q32. The term glycolysis has originated from Greek words (A) Glykos and lysis (B) Glycose and lysis (C) Glyco and lysis (D) Glucose and lysis.

Q33. When one molecule of glucose undergoes glycolysis aerobically, last stable product will be (A) One molecule of pyruvic acid (B) Two molecules of pyruvic acid (C) Three molecules of pyruvic acid (D) Four molecules pyruvic acid.

Q34. During EMP pathway, ATP is produced through (A) Oxidative phosphorylation (B) Cyclic phosphorylation

13

(C) Substrate level phosphorylation (D) None of the above.

Fermentation / Anaerobic Respiration Q35. During the formation of bread, it

becomes porous due to release of CO2 by the action of :- (A) Yeast (B) Bacteria (C) Virus (D) Protozoans

Q36. In alcohol fermentation :- (A) Triose phosphate is the electron

donor, while acetaldehyde is the electron acceptor

(B) Triose phosphate is the electron donor, while pyruvic acid is the electron acceptor

(C) There is no electron donor (D) Oxygen is the electron acceptor

Q37. Conversion of pyruvic acid into ethyl alcohol is mediated by – (A) Phosphatase (B) Dehydrogenase (C) Decarboxylase & dehydrogenase (D) Catalase

Q38. Enzyme pyruvate decarboxylase converts pyruvate into (A) Acetyl CoA (B) Acetaldehyde (C) Acetamide (D) Propionic acid.

Q39. Alcohol dehydrogenase acts on to produce ethyl alcohol (A) Sucrose (B) Starch (C) Glucose (D) Acetaldehyde.

Q40. The process after glycolysis in anaerobic respiration is known as (A) Fermentation (B) Respiration (C) Krebs cycle (D) Decomposition.

Q41. In the production of ethanol, pyruvic acid is first converted to acetaldehyde by the enzyme (A) Alcohol oxidase (B) Alcohol dehydrogenase (C) Pyruvate dehydrogenase (D) Pyruvate decarboxylase

Q42. Lactic acid is formed by the process of (A) Fermentation (B) HMP pathway (C) Glycolysis (D) None of these.

Q43. End products of fermentation are (A) ATP (B) Ethanol + CO

2 + ATP

(C) Ethyl alcohol + CO2 + H

2O + ATP

(D) Pyruvic acid + CO2,

Q44. Krebs’ cycle begins with the reaction : (A) Citric acid + Acetyl coenzyme A (B) Oxaloacetic acid + Pyruvic acid (C) Oxaloacetic acid + citric acid (D) Oxaloacetate + Acetyl coenzyme A

Q45. Which enzyme converts glucose into alcohol? (A) Invertase (B) Lipase (C) Zymase (D) Diastase.

Q46. How many ATP molecules are obtained from fermentation of 1 molecule of glucose? (A) 2 (B) 3 (C) 4 (D) 5

Q47. During lactic acid fermentation. (A) O2 is used, CO2 is liberated

(B) Neither O2 is used, nor CO2 is

liberated (C) O2 is used, CO2 is not liberated

(D) O2 is not used, CO2 is liberated.

Q48. Anaerobic respiration in Yeast yields (A) Ethanol and CO2

(B) Lactic acid and O2

(C) CO2 and water

(D) Pyruvic acid and O2 Q49. Select a suitable name for this process

C6H

12O

6 + 2 ADP + 2Pi 2C

2H

5OH + CO

2 + 2 ATP

(A) Photorespiration (B) Lactate fermentation (C) Aerobic respiration (D) Alcoholic fermentation.

Aerobic Respiration (Link reaction and Tricarboxylic Acid Cycle/Krebs’ Cycle) Q50. Number of ATP produced from one

pyruvic acid during conversion to acetyl CoA – (A) 6 (B) 3 (C) 12 (D) 15

Q51. An example of competitive inhibition of an enzyme is the inhibition of : (A) Succinic dehydrogenase by malonic

acid (B) Cytochrome oxidase by cyanide (C) Hexokinase by glucose - 6

phosphate (D) Carbonic anhydrase by carbon -

dioxide Q52. The formation of Acetyl Co-A from

pyruvic acid is the result of its (A) Reduction

14

(B) Dehydration (C) Phosphorylation (D) Oxidative decarboxylation

Q53. Pyruvate dehydrogenase complex is used in converting – (A) Pyruvate to glucose (B) Glucose to pyruvate (C) Pyruvic acid to lactic acid (D) Pyruvate to acetyl Co-A

Q54. The first member of TCA cycle is (A) Oxalo succinic acid (B) Oxalo acetic acid (C) Citric acid (D) Cis-aconitic acid

Q55. Most of the energy of the carbohydrates is released by oxidation when (A) Pyruvic acid is converted into CO2

and H2O (B) Pyruvic acid is converted into acetyl

Co-A (C) Sugar is converted into pyruvic acid (D) Glucose is converted into alcohol

and CO2 Q56. Respiratory enzymes are localised in

(A) Ribosomes (B) Chloroplast (C) Mitochondria (D) none of the above

Q57. How many ATP equivalents are produced by the oxidation of succinate into fumarate? (A) 1 ATP (B) 2 ATP (C) 4 ATP (D) 3 ATP

Q58. Product formed by the activity of malic dehydrogenase is (A) Fumaric acid (B) Malic acid (C) Oxaloacetic acid (D) Succinic acid

Q59. Which of the following is 5 -carbon compound of Krebs’ cycle? (A) Citric acid (B) Fumaric acid (C) Oxalosuccinic acid

(D) - Ketoglutaric acid Q60. Succinate dehydrogenase catalyses the

formation of

(A) FADH2 FAD

(B) FAD FADH2

(C) NAD+ NADH

(D) NADH.H+ FADH2 Q61. Acceptor of acetyl Co-A in Krebs’-cycle

is (A) Malic acid (B) Fumaric acid

(C) –ketoglutaric acid (D) Oxalo acetic acid

Q62. In which one of the following do the two names refer to one & the same thing :- (A) Krebs’ cycle and Calvin cycle (B) Tricarboxylic acid cycle and citric

acid cycle (C) Citric acid cycle and Calvin cycle (D) Tricarboxylic acid cycle and urea

cycle Q63. Oxidative decarboxylation of pyruvic acid

occurs inside (A) Cytoplasm (B) Outer mitochondrial chamber (C) Outer mitochondrial membrane (D) Mitochondrial matrix.

Q64. Pyruvic acid, the key product of glycolysis, can have many metabolic fates. Under aerobic condition it forms (A) Lactic acid (B) CO

2 + H

2O

(C) Acetyl CoA + CO2

(D) Ethanol + CO2, Q65. Choose the correct statement

(A) Pyruvate is formed in the mitochondrial matrix

(B) During the conversion of succinyl CoA to succinic acid a molecule of ATP is synthesized

(C) Oxygen is vital in respiration for removal of hydrogen

(D) There is complete breakdown of glucose in fermentation.

Q66. Match the following and choose the correct option from those given

Column A Column B

A Molecular

oxygen

Ketoglutaric

acid

B Electron

acceptor

Hydrogen

acceptor

C Pyruvate

dehydrogenase

Cytochrome c

D Decarboxylation Acetyl CoA

Q67. Single turn of citric acid cycle yields (A) 2 FADH

2, 2 NADH2, 2 GTP

(B) 1 FADH2, 2 NADH2, 1 GTP

(C) 1 FADH2, 3 NADH2, 1 GTP

(D) 1 FADH2, 1 NADH2, 2 GTP.

Q68. Identify from the following, the compound that links glycolysis and Krebs’ cycle (A) Oxalo acetic acid (B) Pyruvic acid (C) Lactic acid

15

(D) Acetyl CoA. Q69. Pyruvate dehydrogenase is used to

convert (A) Glucose to pyruvate (B) Pyruvic acid into lactic acid (C) Pyruvate to acetyl CoA (D) Pyruvate to glucose.

Q70. Choose the correct combination of labelling the number of carbon compounds in the substrate molecules, involved in the citric acid cycle.

(A) (a) 4C, (b) 6C, (c) 5C, (d) 4C, (e) 4C (B) (a) 6C, (b) 5C, (c) 4C, (d) 3C, (e) 2C (C) (a) 2C, (b) 3C, (c) 4C, (d) 5C, (e) 6C (D) (a) 4C, (b) 5C, (c) 6C, (d) 4C, (e) 4C (E) (a) 4C, (b) 6C, (c) 4C, (d) 4C, (e) 4C

Q71. Which one is not correct about Krebs’ cycle? (A) It occurs in mitochondria (B) It starts with six carbon compound (C) It is also called citric acid cycle (D) The intermediate compound which

links glycolysis with Krebs cycle is malic acid.

Q72. Succinate + FAD gives rise to......+....... (A) Fumarate + FADH

2

(B) Malate + NADH2

(C) Isocitrate + NADH2

(D) Citrate + H2O.

Q73. Biological oxidation in Krebs’ Cycle involves (A) CO (B) CO

2

(C) O2

(D) N2

Q74. All enzymes of TCA cycle are located in the mitochondrial matrix except one which is located in inner mitochondrial membranes in eukaryotes and in cytosol in prokaryotes. This enzyme is (A) Malate dehydrogenase (B) Isocitrate dehydrogenase (C) Succinate dehydrogenase (D) Lactate dehydrogenase.

Q75. Match the number of carbon atoms given in List-I with that of the compounds given in List-II and select the correct option

List – I List – II

(a) 4C-Compound 1. Acetyl CoA (b) 2C-Compound 2. Pyruvate

(c) 5C-Compound 3. Citric acid (d) 3C-Compound 4. -ketoglutaric

acid

5. Malic acid

(A) (a)-2, (b)-5, (c)-3, (d)-1 (B) (a)-5, (b)-1, (c)-4, (d)-2 (C) (a)-3, (b)-1, (c)-4, (d)-2 (D) (a)-5, (b)-3, (c)-1, (d)-2

Q76. In Krebs’ cycle a 6-c compound is formed by the combination of acetyl Co-A and (A) Malic acid (B) Citric acid (C) Succinic acid (D) Oxaloaceticacid.

Q77. In which of the following steps of Krebs cycle CO

2 is evolved?

(A) Isocitric acid Oxalosuccinicacid

(B) Oxalosuccinicacid -ketoglutaric acid

(C) SuccinicacidFumaric acid

(D) Malic Acid Oxaloaceticacid. Q78. Which of the following enzymes is not

used in Krebs’ cycle? (A) Aconitase (B) Aldolase (C) Decarboxylase (D) Fumarase.

Q79. Oxalosuccinic acid, an intermediary compound of Krebs’ cycle is a (A) 6 carbon compound (B) 5 carbon compound (C) 3 carbon compound (D) 4 carbon compound.

Q80. In which of the following, reduction of NAD does not occur?

(A) Pyruvic acid Acetyl Coenzyme

(B) Isocitric acid -ketoglutaric acid

(C) Malic acid Oxaloacetic acid

(D) Succinic acid Fumaric acid. Q81. Match the compounds given in column I

with the number of carbon atoms present in them which are listed under column II. Choose the answer which gives the correct combination of alphabet of the two columns.

Column – I Column - II

(a) Oxaloacetate (p) 6-C compound

(b)Phosphoglyceraldehyde (q) 5-C compound

(c) Isocitrate (r) 4-C

16

compound

(d) -ketoglutarate (s) 3-C compound

(t) 2-C compound

(A) (a)–(s), (b)–(t), (c)–(q), (d)–(r). (B) (a)–(r), (b)–(s), (c)–(p), (d)–(q). (C) (a)–(r), (b)–(t), (c)–(p), (d)–(q). (D) (a)–(q), (b)–(s), (c)–(P), (d)–(t).

Q82. FAD is electron acceptor during oxidation in which of the following?

(A) -ketoglutarateSuccinyl CoA

(B) Succinic acid Fumaric acid

(C) Succinyl CoA Succinic acid

(D) Fumaric acid Malic acid. Q83. Direct ATP yield of aerobic respiration

during Krebs’ cycle per glucose molecule is (A) 2 ATP molecules (B) 8 ATP molecules (C) 36 ATP molecules (D) 19 ATP molecules

Q84. During Krebs’ cycle energy from glucose is mostly transferred to (A) ADP (B) water (C) NADPH (D) NADH and FADH

2

Q85. During one Krebs’ cycle number of CO2

molecules released is (A) 1 (B) 2 (C) 3 (D) 4

Q86. Which one does not donate phosphate in glycolysis? (A) ATP (B) NADP (C) 1, 3-biphosphoglycerate (D) Phosphoenol pyruvate

Q87. F1particle of oxysome

(A) Releases proton energy (B) Utilises proton energy (C) Has no role in energy consumption (D) Lies in outer chamber

Q88. In Citric acid cycle, decarboxylation

occurs when

(A) Citric acid converts to -ketoglutaric acid

(B) Malic acid converts to oxaloacetic acid

(C) Succinic acid converts to malic acid (D) Oxaloacetic acid converts to citric

acid. Q89. Enzymes of TCA cycle are present in

(A) Ribosome (B) Chloroplasts (C) Mitochondria

(D) Nucleus. Q90. In Krebs’ cycle, OAA accepts acetyl CoA

to form (A) Citric acid (B) Oxalosuccinate (C) Fumarate (D) Succinyl CoA.

Q91. Which of the following is a 4-carbon compound? (A) Oxaloacetic acid (B) Citric acid (C) Phosphoenol pyruvate (D) Ribulosebisphosphate.

Q92. Which of the following processes of Krebs’ cycle is associated with both the processes of decarboxylation and dehydrogenation

(A) Succinate Fumarate,

Fumarate Malate

(B) Malate Oxaloacetate,

Succinate Fumarate

(C) -ketoglutaric acid Succinate,

Malate Oxaloacetate

(D) Isocitrate-ketoglutaricacid,

-ketoglutaric acid Succinate. Q93. Arrange the following compounds of

Krebs cycle in ascending order of carbon atoms they possess (a) Succinic acid (b) Acetyl CoA

(c) -ketoglutaric acid (d) Citric acid. (A) a - d - c - b (B) c - a - d - b (C) b - a - c - d (D) d - c - b - a.

Q94. Substrate level phosphorylation occurs in TCA cycle during conversion of (A) Oxaloacetic acid to citric acid (B) SuccinylCoA to succinic acid (C) Succinic acid to fumaric acid (D) Fumaric acid to malic acid.

Electron Transport System (Ets) and Oxidative Phosphorylation Q95. The deficiencies of micronutrients, not

only affects growth of plants, but also vital functions such as photosynthetic and mitochondrial electron flow.Among the list given below, which group of three elements shall affect most, both photosynthetic and mitochondrial electron transport: (A) Cu, Mn, Fe (B) Co, Ni, Mo (C) Mn, Co, Ca (D) Ca, K, Na

Q96. Chemiosmotic theory of ATP synthesis in the chloroplast and mitochondria is based on :

17

(A) Proton gradient (B) Accumulation of K ions (C) Accumulation of Na ions (D) Membrane potential

Q97. Which of the following ETS complex is inhibited by cyanide? (A) Complex II (B) Complex V (C) Complex IV (D) Complex III

Q98. In the electron transport chain during terminal oxidation, the cytochrome, which donates electrons to O2 is? (A) Cytochrome-b (B) Cytochrome-c (C) Cytochrome-a3 (D) Cytochrome-f

Q99. Which component of ETS is mobile carrier? (A) UQ (CO-Q) (B) Cyt. - a (C) Cyt. - b (D) Cyt. – f

Q100. Cytochrome a3 contains (A) Iron only (B) Iron and Copper (C) Copper only (D) One iron and two copper centres.

Q101. In oxidative phosphorylation, one FADH2 produces (A) 3 ATP (B) 4 ATP (C) 2 ATP (D) One ATP.

Q102. The ultimate electron acceptor of

respiration in an aerobic organism is (A) Cytochrome (B) Oxygen (C) Hydrogen (D) Glucose.

Q103. Electron Transport System (ETS) is. located in mitochondrial (A) Outer membrane (B) Inter membrane space (C) Inner membrane (D) Matrix.

Q104. Which of the following does not function as an electron carrier? (A) Coenzyme (B) H

2O

(C) Cytochrome-a (D) Cytochrome-a3

Q105. In oxidative phosphorylation the last three steps are as follows

Q Cyt.cCytaa3 O2

(A) Q Cytc is H+ absorbing site

(B) Cytaa3 O2. H+ yielding site

(C) Q Cytc is H+ yielding site and

Cytaa3 O2 is H

+ absorbing site

(D) No H+ is absorbed or released.

Q106. In electron transport system (ETS), which of the following cytochrome reacts with oxygen? (A) Cyt b (B) Cytaa

3

(C) Cyt b6

(D) Cyt f Q107. Both photosynthesis and respiration

require (A) Chloroplasts (B) Cytochromes (C) Mitochondria (D) Sunlight

Q108. Mitochondrial ATP synthesis occurs in (A) Outer membrane (B) Matrix (C) In between cristae (D) Surface of cristae.

Q109. Which of the following processes make direct use of oxygen? (A) Glycolysis (B) Fermentation (C) Electron transport (D) Krebs citric acid cycle

Q110. Terminal acceptor of electrons in ETC chain is (A)O

2

(B) Cytochrome (C) Flavoprotein (D) H

2O.

Q111. There is no transfer of electrons from Cyt.b to Cyt. c as (A) Electrons are transported in pairs (B) Electrons do not have affinity for

cytochromes (C) Energy is not available (D) The two are not nearby.

Q112. The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed because (A) A proton gradient forms across the

inner membrane (B) There is a change in the permeability

of the inner mitochondrialmembranetowards adenosine diphosphate (ADP)

(C) High energy bonds are formed in mitochondrial proteins

(D) ADP is pumped out of the matrix into inter-membrane space.

Q113. Consider the following statements (1) Copper is present in cytochrome

oxidase (2) Pantothenic acid is the precursor of

CoA

18

(3) Thymine pyrophosphate is the prosthetic group in decarboxylases

(4) Zinc is present in RNA and DNA polymerases.

(A) 1, 2, 3 correct (B) 1, 2 correct (C) 2, 4 correct (D) 1, 3 correct.

Q114. In mitochondria, enzyme cytochrome oxidase is present in (A) Perimitochondrial space (B) Outer membrane (C)Inner membrane (D) Matrix.

Q115. Oxidative phosphorylation refers to (A) Anaerobic production of ATP (B) The citric acid cycle production of

ATP (C) Production of ATP by chemiosmosis (D) Alcoholic fermentation.

Q116. Which one of the following is complex V of the ETS of inner mitochondrial membrane? (A) NADH dehydrogenase (B) ATP synthase (C) Succinate dehydrogenase (D) Ubiquinone

Q117. Final product of ETS of mitochondria is (A) H2O (B) H+ (C) Electrons (D) All the above.

Q118. ATP is synthesised in (A) Ion channels (B) Plasmalemma (C) F

0 particles

(D) F1 particles.

Q119. The following is a scheme showing the electron transport system. Identify the electron carrier molecules indicated as a and b. Choose the correct option

(A) a = Coenzyme Q, b = Cytochrome c (B) a = Cytochrome c, b = Coenzyme Q (C) a = Fe-S protein, b = FMN (D) a = FMN, b = Fe-S protein.

Q120. Which of the following membrane bound complexes in mitochondria is not a protein pump? (A) Cytochrome b - c (B) Cytochrome c oxidase (C) NADH dehydrogenase (D) Succinate dehydrogenase.

Q121. How many ATP molecules can be produced through oxidative phosphorylation of 2 NADH

2 and 3 FADH

2

(A) 15 (B) 24 (C) 6 (D) 12

Q122. In the electron transport chain, the first ATP molecule is generated when hydrogen passes from (A) FMN to NAD (B) FMN to CoQ (C) NAD to FMN (D) NAD to CoQ.

Q123. Chemiosmotic theory of ATP synthesis in the mitochondrion is based on (A) K+ gradient (B) H+ gradient (C) Na+ gradient (D) Ca2+ gradient

Q124. Which one is mitochondrial marker enzyme? (A) Aldolase (B) Amylase (C) Pyruvate dehydrogenase (D) Succinic dehydrogenase.

Q125. Given below is an electron acceptor. Mention its status which is labelled as a

(A) Oxidised (B) Reduced (C) Phosphorylation (D) Hydrated.

Respiratory Balance Sheet Q126. How many ATP molecules produced

from the complete oxidation of a molecule of active acetate or acetyl CoA? (A) 38 ATP (B) 15 ATP (C) 12 ATP (D) 4 ATP

Q127. Substrate level net gain of ATP molecules during complete oxidation of 1 molecule of glucose– (A) 8 ATP (B) 6 ATP (C) 4 ATP (D) 2 ATP

Q128. There is gain of how many ATP in aerobic respiration of eukaryotic cell? (A) 28 ATP (B) 36 ATP (C) 20 ATP (D) 40 ATP

Q129. Which of the following is link between carbohydrate, fat & Protein metabolism? (A) CO2 (B) Acetyl Co-A

Cy++

Cy+++a

(C) Pyruvic acid (D) Citric acid

Q130. Number of ATP molecules produced from 1 glucose molecule in aerobic respiration is (A) 36 (B) 32 (C) 30 (D) 28

Q131. One molecule of pyruvic maximum of (A) 8 ATP (B)12 ATP (C) 15 ATP (D) 36 ATP

Q132. The minimum oxygen concentration at which aerobic respiration can continue is (A) Transition point (B) Extinction point (C) Pasteur effect (D) Compensation point.

Q133. How many molecules of NADH

produced when four molecules of phosphoglyceraldehyde are converted into four molecules of pyruvate(A) 2 (B) 6 (C) 8 (D) 4

Q134. It is simplified representation of fate of glucose in aerobic and anaerobic respiration. Identify the products labelled as a, b, c and d

(A) a - CO2 + H2O, b - pyruvic acid, c

ethyl alcohol + CO2, d

(B) a - pyruvic acid, b -

lactic acid, d - ethyl alcohol + CO

(C) a - pyruvic acid, b -

ethyl alcohol + CO2, d

(D) a - pyruvic acid, b - CO2, c - lactic acid, d

Q135. In anaerobic respiration the number of ATP molecules produced are(A) 1 (B) 2 (C) 3 (D) 8

Q136. How many PGAL are produced by glycolysis of 3 molecules of glucose?

Number of ATP molecules produced from 1 glucose molecule in aerobic

One molecule of pyruvic acid can yield a

The minimum oxygen concentration at which aerobic respiration can continue

How many molecules of NADH

2 are

produced when four molecules of phosphoglyceraldehyde are converted into four molecules of pyruvate?

It is simplified representation of fate of glucose in aerobic and anaerobic respiration. Identify the products

pyruvic acid, c -

, d-Iactic acid

CO2 + H2O, c -

ethyl alcohol + CO2

CO2 + H2O, c -

, d - lactic acid

ethyl alcohol + lactic acid, d - CO2 + H2O.

In anaerobic respiration the number of ATP molecules produced are

How many PGAL are produced by glycolysis of 3 molecules of glucose?

How many ATP are released by respiration of these PGAL till formation of CO

2and H

2O?

(A) 4 PGAL–40 ATP (B) 6 PGAL–120 ATP(C) 4 PGAL–80 ATP(D) 6 PGAL–160 ATP

Respiratory Quotient Q137. R.Q. of lactic acid fermentation is

(A) Zero (B) Less than one (C) More than one (D) Infinity.

Q138. R.Q. is infinity in case of(A) Respiration of Fats (B) Respiration of proteins(C) Aerobic respiration of carbohydrates(D) Alcoholic fermentation.

Q139. If RQ is 0·6 in a respiratory metabolism, it would mean that(A) Carbohydrates are used as

respiratory material(B) Organic acids are used as

substrate (C) The oxidation of the respiratory

substrate consumed more oxygen than the amount of CO

(D) The oxidation of respiratory substrate consumed less oxygen than the amount of CO

Q140. 2 C51H98O6 + 146 O

H2O. The RQ for above reaction is

(A) 0·7 (B) 1 (C) 1·45 (D) 1·62.

Q141. The respiratory quotient (RQ) or respiratory ratio is

(A) Volumeof O evolved

RQ=Volumeof CO evolved

(B) 2Volumeof O consumed

RQ=Volumeof CO evolved

(C) 2Volumeof O consumed

RQ=Volumeof O evolved

(D) 2

Volumeof CO evolvedRQ=

Volumeof O consumed

Q142. The Respiratory Quotient (R.Q.) of some

of the compounds are 4, 1 and 0·7. These compounds are identified respectively as (A) Malic acid, palmitic acid and

tripalmitin

19

How many ATP are released by respiration of these PGAL till formation

40 ATP 120 ATP 80 ATP 160 ATP

R.Q. of lactic acid fermentation is

in case of Respiration of Fats Respiration of proteins Aerobic respiration of carbohydrates Alcoholic fermentation.

If RQ is 0·6 in a respiratory metabolism, it would mean that

Carbohydrates are used as respiratory material Organic acids are used as respiratory

The oxidation of the respiratory substrate consumed more oxygen than the amount of CO

2 released

The oxidation of respiratory substrate consumed less oxygen than the amount of CO

2 released.

+ 146 O2 102 CO2 + 98

RQ for above reaction is

The respiratory quotient (RQ) or

2

2

Volumeof O evolved

Volumeof CO evolved

2

2

Volumeof O consumed

Volumeof CO evolved

2

2

Volumeof O consumed

Volumeof O evolved

2

2

Volumeof CO evolved

Volumeof O consumed

The Respiratory Quotient (R.Q.) of some of the compounds are 4, 1 and 0·7. These compounds are identified

Malic acid, palmitic acid and

20

(B) Oxalic acid, carbohydrate and tripalmitin

(C) Tripalmitin, malic acid and carbohydrate

(D) Palmitic acid, carbohydrate and oxalic acid

Q143. The respiratory quotient during cellular respiration would depend on (A) The nature of enzymes involved (B) The nature of the substrate (C) The amount of carbon dioxide

released (D) The amount of oxygen utilized.

Q144. Consider the following statements concerning respiration and choose the correct option

(a) Glycolysis occurs in the cytoplasm of the cell

(b) Aerobic respiration takes place within the mitochondria

(c) Electron transport system is present in outer mitochondrial membrane

(d) C51H98O6 is the chemical formula of tripalmitin fatty acid.

(e) 2

2

Volumeof O evolvedRespiratory Quotient=

Volumeof CO consumed

Of the above statements (A) a, b, and d are correct (B) b, c, and d are correct (C) c, d, ande are correct (D) b, d, and e are correct

EXERCISE – 2 (PYQ)

RESPIRATION IN PLANTS

Q1. Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these : [2005] (A) enhance oxidative metabolism (B) are conjugated proteins (C) are exclusively synthesized in the

body of a living organism (D) help in regulating metabolism

Q2. During which stage in the complete oxidation of glucose is the greatest number of ATP molecules formed from ADP? [2005] (A) Conversion of pyruvic acid to acetyl

CoA (B) Electron transport chain (C) Glycolysis (D) Krebs’ cycle

Q3. The catalytic efficiency of two differentenzyme can be compared by the :[2005]

(A) The Km value

(B) The pH optimum value

(C) Formation of the product

(D) Molecular size of the enzyme

Q4. The graph given below shows the effect of substrate concentration on the rate of reaction of the enzyme green-gram-phosphatase. What does the graph indicates? [2005] [2005] (A) The rate of enzyme reaction is

directly proportional to the substrate concentration.

(B) Presence of an enzyme inhibitor in the reaction mixture

(C) Formation of an enzyme substrate complex

(D) At higher substrate concentration the pH increases

Q5. Curing of tea leaves is brought about by

the activity of – [2006]

(A) viruses (B) fungi

(C) bacteria (D) mycorrhiza

Q6. Which of the following statements regarding mitochondrial membrane is NOT correct? [2006] (A) The inner membrane is highly

convoluted forming a series of infolding

(B) The outer membrane resembles a sieve

(C) The outer membrane is permeable to all kinds of molecules

(D) The enzymes of the electron transfer chain are embedded in the outer membrane.

Q7. 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? [2006]

(A) 57 (B) 1

OO

Substrate concentration

Velo

city

21

(C) 2 (D) 30

Q8. The overall goal of glycolysis, Krebs cycle and the electron transport system is the formation of:- [2007]

(A) Nucleic acids (B) ATP in small stepwise units

(C) ATP in one large oxidation reaction

(D) Sugars

Q9. All enzymes of TCA cycle are located in the mitochondrial matrix except one which is located in inner mitochondrial membrane in eukaryotes and in cytosol in prokaryotes. This enzyme is:-[2007]

(A) Succinate dehydrogenase (B) Lactate dehydrogenase

(C) Isocitrate dehydrogenase

(D) Malate dehydrogenase

Q10. Which one of the following mammalian cells are not capable of metabolising glucose to carbon-dioxide aerobically? [2007] (A) Red blood cells

(B) White blood cells

(C) Unstriated muscle cells (D) Liver cells

Q11. The energy-releasing process in which the substrate is oxidised without an external electron acceptor is called :-

[2008]

(A) Aerobic respiration

(B) Glycolysis

(C) Fermentation

(D) Photorespiration

Q12. In germinating seeds fatty acids are degraded exclusively in the:- [2008] (A) Peroxisomes (B) Mitochondria

(C) Proplastids

(D) Glyoxysomes

Q13. Aerobic respiratory pathway isappropriatelytermed :-[2009]

(A) Parabolic (B) Amphibolic

(C) Anabolic (D) Catabolic

Q14. In mitochondria, protons accumulate in the : [2011] [2011]

(A) Matrix

(B) Outer membrane

(C) Inner membrane

(D) Intermembrane space

Q15. Which of the following cell organelles is responsible for extraction of energy from carbohydrates to form ATP? [2017] [2017]

(A) Lysosome

(B) Ribosome

(C) Chloroplast

(D) Mitochondrion

Q16. Which statement is wrong for Krebs’ cycle? (A) There are three points in the cycle

whereNAD+ is reduced to NADH+H+ (B) There is one point in the cycle where

FAD+ is reduced to FADH2.

(C) During conversion of Succinyl CoA to succinic acid, a molecule of GTP is synthesised.

(D) The cycle starts with condensation of acetyl group (acetylCoA) with pyruvic acid to yield citric acid.

Q17. What is the role of NAD+ in cellular respiration? [2018] (A) It is a nucleotide source for ATP

synthesis. (B) It functions as an electron carrier. (C) If functions as an enzyme. (D) It is the final electron acceptor for

anaerobic respiration. Q18. Which of these statements is incorrect?

[2018] (A) Glycolysis operates as long as it is

supplied with NAD that can pick up hydrogen atoms.

(B) Glycolysis occurs in cytosol. (C) Enzymes of TCA cycle are present in

mitochondrial matrix (D) Oxidativephosphorylationtakes place in

outer mitochondrial membrane. Q19. What is the role of NAD+ in cellular

respiration? [2019] (A) It is a nucleotide source for ATP

synthesis (B) It functions as an electron carrier (C) It functions as an enzyme (D) It is the final electron acceptor for

anaerobic respiration. Q20. Which of these statements is incorrect?

[2019] (A) Glycolysis operates as long as it is

supplied with NAD that can pick up hydrogen atoms.

(B) Glycolysis occurs in cytosol (C) Enzymes of TCA cycle are present in

mitochondrial matrix. (D) Oxidative phosphorylation takes

place in outer mitochondrial membrane

Q21. The number of substrate level phosphorylation in one turn of citric acid cycle is : [2020] (A) Two (B) Three

22

(C) zero (D) one

Q22. Pyruvate dehydrogenase activity during aerobic respiration requires :

[2020 Re-exam] (A) Calcium

(B) Iron (C) Cobalt (D) Magnesium

Skill Booster 1

Q1. What is the importance of respiration in organisms?

(A) It provides oxygen to plant

(B) It liberates energy

(C) It liberates CO2

(D) All of the above

Q2. Which component of ETS is mobile, e–

carrier?

(A) UQ (CO-Q)

(B) Cyto a (C) Cyto - b (D) Cyto – f

Q3. R.Q. is less than one at the time of respiration of -

(A) Starch

(B) Sugarcane (C) Glucose

(D) Ground nut

Q4. Number of ATP produced from one pyruvic acid during conversion to acetyl Co-A-

(A) 6

(B) 3

(C) 12

(D) 15

Q5. The link between Glycolysis and Krebs cycle is

(A) Citric acid

(B) Malic acid

(C) Fumaric acid

(D) Acetyl co-enzyme-A

Q6. Succinyl Co-A is related to -

(A) Krebs cycle

(B) Calvin cycle

(C) Glycolate cycle

(D) HMP-cycle

Q7. According to chemiosmotic theory of P.Mitchell (1978), ATPs are synthesised on membrane due to the -

(A) Proton gradient

(B) Electron gradient

(C) Osmosis

(D) From H2SO

4

Q8. Conversion of pyruvic acid into ethyl alcohol is mediated by -

(A) Phosphatase

(B) Dehydrogenase

(C) Decarboxylase & dehydrogenase

(D) Catalase

Q9. The formation of Acetyl Co-A from pyruvic acid is the result of its -

(A) Reduction

(B) Dehydration

(C) Phosphorylation

(D) Oxidative decarboxylation

Q10. Pyruvate dehydrogenase complex is used in converting-

(A) Pyuvate to glucose

(B) Glucose to pyruvate

(C) Pyruvic acid to lactic acid (D) Pyruvate to acetyl Co-A

Q11. The first compound of TCA cycle is -

(A) Oxalo succinic acid

(B) Oxalo acetic acid

(C) Citric acid

(D) Cisaconitic acid

Q12. Oxidation of one molecule of glucose in aerobic respiration result in the formation of-

(A) 36 ATP molecules

(B) 40 ATP molecules

(C) 3 ATP molecules

(D) 15 ATP molecules

Q13. In the electron transport chain during terminal oxidation, the cytochrome, which donated electrons to O2is?

(A) Cytochrome-b

(B) Cytochrome -C

(C) Cytochrome -a3

(D) Cytochrome -f

Q14. Alternate name of Krebs cycle is -

(A) Glyoxylate cycle

(B) Glycolate cycle

(C) Citric acid cycle

(D) EMP Pathway

23

Q15. Respiration in plants

(A) Occurs only during day

(B) Results in the formation ofvitamins

(C) Is characteristic of all living cells

(D) Often requires CO2

Q16. The cell organelle in, which aerobicrespiration occurs -

(A) Ribosome

(B) Mitochondria

(C) Lysosomes

(D) Chloroplast

Q17. The incomplete breakdown of sugars in anaerobic respiration result in the formation of -

(A) Fructose and water

(B) Glucose and carbon dioxide

(C) Alcohol and CO2

(D) Water and CO2

Q18. A.T.P. is

(A) A hormone

(B) A protein

(C) An enzyme which brings about oxidation (D) A molecule which contain high

energy bond Q19. Cytochromes are concerned with -

(A) Protein synthesis

(B) Cellular digestion

(C) Cell division

(D) Cell-respiration

Q20. Krebs’ cycle takes place in -

(A) Vesicles of E.R

(B) Mitochondrial matrix

(C) Dictyosomes

(D) Lysosomes

Q21. In respiration pyruvic acid is - (A) Formed only when oxygen is

available (B) One of product of Krebs’ cycle (C) Broken down into Acetyl Co-A and

CO2

(D) a result of protein break down Q22. Most of the energy of the carbohydrates

is released by oxidation when - (A) Pyruvic acid is converted into CO2

and H2O (B) Pyruvic acid is converted into acetyl

Co-A

(C) Sugar is converted into pyruvic acid (D) Glucose is converted into alcohol

and CO2 Q23. The universal hydrogen acceptor is -

(A) NAD

(B) ATP

(C) Co-A

(D) FMN

Q24. Iron-porphyrin protein complex occurs in -

(A) phytochrome

(B) cytochrome

(C) chlorophyll

(D) both (A) and (C)

Q25. Fermentation is conducted by

(A) All bacteria

(B) All fungi

(C) Some fungi and some bacteria

(D) All micro organism

Q26. Respiration is an -

(A) Exothermic process (B) Endothermic process (C) Anabolic process (D) None of these

Q27. How many times CO2released in aerobic

respiration -

(A) One or two

(B) Three

(C) Six

(D) Twelve

Q28. Respiratory quotient is expressed as -

(A) O/CO2

(B) CO2/O

2

(C) O2/H

2O

(D) CO2-O

2

Q29. The value of RQ at compensation point is -

(A) One

(B) More than one

(C) Less than one

(D) Infinite

Q30. The value of RQ of starved cell is -

(A) Zero

(B) Less than one (C) 1

(D) infinite

SKILL BOOSTER 2

Q1. Protoplasmic proteins are used as a respiratory substrate only when - (A) Carbohydrates are absent (B) Fats are absent

(C) Both A &B are absent (D) Fats & carbohydrates are abundant

Q2. The common phase between aerobic & anaerobic respiration is -

24

(A) TCA cycle

(B) Krebs’ cycle

(C) Glycolysis

(D) Photo respiration

Q3. The term ‘’Floating respiration’’ is used when the respiratory substrate is -

(A) Carbohydrates (B) Fats

(C) Both A and B (D) Protein

Q4. Glycolysis give rise to - (A) 8ATP, 2NADH

2, 2 Pyruvate

(B) 2ATP, 2CoA, 2NADH2

(C) 2ATP, 2NADH2, 2 Pyruvate

(D) 2ATP, 2 acetate, 2NADPH2

Q5. The inhibitory effect of the presence of O

2on anaerobic respiration is termed -

(A) Warburg effect (B)Pasteur effect

(C) Emerson’s effect (D) Oxygen effect

Q6. Which of the following ETS complex is inhibited by cyanide -

(A) Complex II (B) Complex V

(C) Complex IV (D) Complex III

Q7. Final e– acceptor of mitochondria is (A) Pyruvate (B) NADP

(C) O2

(D) OAA

Q8. The number of ATP molecules produced from one Krebs’ cycle are -

(A) 12

(B) 30

(C) 38

(D) 40

Q9. How many molecules of ATP are produced per molecule of FADH

2oxidised

-

(A) One

(B) Two

(C) Three

(D) four

Q10. Which of the following cytochrome donated electron to oxygen -

(A) Cyt.-a1

(B)Cyt.-b

(C)Cyt.-a3

(D)Cyt.-c

Q11. The product of aerobic respiration of glucose is -

(A) CO2+ H

2O + ATP

(B) CO2+ Pyruvic acid

(C) CO2+ ethyl alcohol

(D) CO2+ Pyruvic acid + citric acid

Q12. Product formed by the activity of malic dehydrogenase is -

(A) Fumaric acid

(B) Malic acid

(C) Oxaloacetic acid

(D) Succinic acid

Q13. Respiration differs from burning in which of the following?

(A) Energy released in respiration

(B) Oxidation of substance occurs

(C) Enzymes are involved

(D) All the above Q14. Site of Krebs’ cycle in respiration & ATP

synthesis is -

(A) Mitochondrial stroma

(B) Matrix &oxysome

(C) Cytoplasm

(D) None of the above Q15. Cyanide resistant respiration is found in

(A) Homo sapiens

(B) Brassica

(C) Spinach (D) Bacteria

Q16. Ganong’srespirometer used for -

(A) Respiration measuring

(B) R.Q. measuring

(C) Transpiration measuring

(D) All of the above Q17. FADH

2Produced in Kreb’s-cycle from

(A) Isocitrate

(B) -ketoglutarate

(C) succinate (D) malate

Q18. 1 molecule of glucose when oxidised through EMP & TCA-cycle would yield

(A) 30 ATP gross

(B) 40 ATP net

(C) 36 or 38 ATP net

(D) 38 ATP only Q19. What is true for Krebs’ cycle?

(A) GTP/ATP is formed

(B) 2 Decarboxylation

(C) Acetyl Co-A acceptor is OAA

(D) All the above

Q20. Which enzyme break downs the fructose-1, 6-Disphosphate?

(A) Hexokinase

(B) Phosphatase

(C) Aldolase

(D) None

25

Q21. When 2-pyruvic acids form two lactic acid by anaerobic respiration then?

(A) One ATP is lost

(B) 3 ATP is lost

(C) 6 ATP is lost

(D) None

Q22. What is the energy coin of a cell?

(A) DNA

(B) RNA

(C) ATP

(D) Minerals

Q23. During the formation of bread, it becomes porous due to release of CO2 by the action of -

(A) Yeast

(B) Bacterial

(C) Virus

(D) Protozoans

Q24. In alcohol fermentation (A) Triose phosphate is the electron

donor, while acetaldehyde is the electron acceptor

(B) Triose phosphate is the electron donor, while pyruvic acid is the electron acceptor

(C) There is no electron donor (D) Oxygen is the electron acceptor

Q25. How is the energy present in food released during biological oxidation?

(A) In one step, quickly

(B) In two steps, slowly

(C) In different steps, slowly

(D) In different steps, quickly

Q26. What is wrong about respiration? (A) It does not occur in cell

(B) Oxidation occurs without the use of enzymes

(C) Energy is released in one step quickly

(D) All the above Q27. When is NADH

2 formed in glycolysis

(A) During the formation of DiHAPfrom PGAL

(B) During the formation of 1-3 DiPGAL from PGAL

(C) During the formation of 1-3 DiPGAfrom 1-3 DiPGAL

(D) During the formation of PEP from PGA

Q28. When is ATP formed in glycolysis? (A) During the formation of 3-PGA from

1-3 DiPGA (B) During the formation of Pyruvic acid

from PEP (C) Both of above (D) None of the above

Q29. What is the total gain in terms of ATP in glycolysis? (A) Six (B) Four

(C) Eight

(D) Ten

Q30. Why the animals feel fatigue during exercise? (A) Due to accumulation of malic acid (B) Due to accumulation of lactic acid (C) Due to accumulation of pyruvic acid (D) Due to all the above

SKILL BOOSTER 3

Q1. The energy releasing process in which

the substrate is oxidised without an external electron acceptor is called

(A) Aerobic respiration

(B) Glycolysis

(C) Fermentation

(D) Photorespiration

Q2. Aerobic respiratory pathway is appropriately termed

(A) Catabolic

(B) Parabolic

(C)Amphibolic

(D) Anabolic

Q3. Which of the option is correct for photorespiration

(A) In chloroplast, glycerate forms glycine

(B) In peroxisome, glycerate forms phosphoglycolate

(C) In mitochondria, glycine forms serine

(D) In bundle sheath, serine form glycine

Q4. Match the following and choose the correct option from those given below.

Column A Column B

A. Molecular

oxygen

i. -

Ketoglutar

ic acid

B. Electron

acceptor

ii. Hydrogen

acceptor

26

C. Pyruvate

dehydrogenase

iii

.

Cytochro

me C

D. Decarboxylation iv

.

Acetyl Co

A

(A) A-ii, B-iii, C-iv, D-i (B) A-iii, B-iv, C-ii, D-i

(C) A-ii, B-i, C-iii, D-iv

(D) A-iv, B-iii, C-i, D-ii

Q5. Column I contains some enzymes and Column II contains reactions. Match them properly and choose the right answer

Column I Column II

A Hexokinase 1 Conversionof fructose-6 -phosphate to fructose-1-6- diphosphate

B Triose

Phosphate

2 Conversion of glucose toglucose-6-phosphate dehydrogenase

C Phosphogly-ceromutase

3 Conversion of 1, 3

Diphosphoglyceraldehydeto 1,3 diphosphoglyceric

acid

D Phosphofructo-kinase

4 Conversion of 3-phosphogly-

ceric acid to 2-phosphoglyceric acid

(A) A-1, B-2, C-3, D-4

(B) A-2, B-3, C-4, D-1

(C) A-2, B-1, C-3, D-4

(D) A-1, B-5, C-2, D-4

Q6. Match the number of carbon atoms given in Column-I with that of the compounds given in Column-II and select the correct option

Column I Column II

A. 4C Compound 1 Acetyl CoA

B. 2C Compound 2 Pyruvate

C. 5C Compound 3 Citric acid

D. 3C Compound 4 -

ketoglutaric

acid

5. Malic acid

(A)A-2, B-5, C-3, D-1

(B)A-5, B-1, C-4, D-2

(C) A-3, B-1, C-4, D-2

(D)A-5, B-3, C-1, D-2

Q7. Choose the correct combination of labelling the molecules involved in the pathway of anaerobic respiration in yeast

(A) A – Ethanol,B - CO

2,C –

Acetaldehyde (B) A - CO

2,B - Ethanol, C –

Acetaldehyde (C) A - CO

2,B - Acetaldehyde, C –

Ethanol (D) A – Ethanol,B - Acetaldehyde, C –

CO2

Q8. In which of the following reaction of glycolysis, a molecule of water is removed from the substrate

(A) Fructose - 6 - phosphate fructose 1, 6 - bisphosphate

(B) 3 - phosphate glyceraldehyde 1, 3 –bisphosphoglyceric acid

(C) PEP Pyruvic acid

(D) 2 - Phosphoglycerate PEP

(E) Glucose glucose 6 - phosphate Q9. Which process does the following

equation represent

C6H

12O

6 + 2NAD+ + 2ADP + 2Pi

2CH3 - CO - COOH + 2NADH2 + 2ATP

(A) Complete glycolysis

(B) Complete aerobic respiration

(C) Complete anaerobic respiration

(D) Complete fermentation

Q10. Consider the following statements with respect to respiration (a) Glycolysis occurs in the cytoplasm of

the cell (b) Aerobic respiration takes place

Within the mitochondria

27

(c) Electron transport system is present in the outer mitochondria membrane

(d) C51H

98O

5 is the chemical formula of

Tripalmitin, a fatty acid (e) Respiratory quotient = Of the above

statements

(A)a andb alone are correct

(B)b and c alone are correct

(C)c, d and e alone are correct

(D)b, d and e alone are correct

Q11. Raw material for respiration is

(A) Glucose& O2

(B) Glucose & CO2

(C) Glucose & Carbon

(D) Glucose & sucrose

Q12. The tissue of highest respiratory activity is

(A) Meristem

(B) Ground tissue

(C) Phloem

(D) Mechanical tissue

Q13. Vitamin serves the function of

(A) An enzyme

(B) A coenzyme

(C) A substrate

(D) A hormone

Q14. What is NADP?

(A) An enzyme

(B) An ion carrier

(C) H2 acceptor coenzyme

(D) A part of t-RNA

Q15. Substrate level ATP molecules gain during complete oxidation of 1 molecule of glucose –

(A) 8 ATP

(B)6 ATP

(C) 4 ATP

(D) 2 ATP

Q16. Site of Krebs’-cycle in respiration &oxidative phosphorylation is –

(A) Mitochondrial stroma

(B) Matrix &oxysome

(C) Cytoplasm

(D) None of the above

Q17. How many molecules of NADH are produced when four molecules of phosphoglyceraldehyde are converted into four molecules of pyruvate?

(A) 2

(B) 6

(C) 8

(D) 4

Q18. What is true for Krebs’ cycle?

(A) GTP/ATP is formed

(B)1 stable product is citric acid

(C)first member of TCA cycle is O.A.A

(D) All the above

Q19. For retting of jute, the fermenting microbe used is :

(A)Helicobactor pylori

(B)Methanophilic bacteria

(C)Streptococcus lacti

(D) Butyric acid bacteria

Q20. Cut surfaces of fruits and vegetables often become dark because (A) Dirty knife makes it dark (B) Oxidation of tannic acid in the

presence of trace of iron from the knife makes it dark

(C) Dust of the air makes it dark (D) None of the above

Q21. An example of competitive inhibition of an enzyme is the inhibition of : (A) Succinic dehydrogenase by malonic

acid (B) Cytochrome oxidase by cyanide (C) Hexokinase by glucose - 6

phosphate (D) Carbonic anhydrase by carbon –

dioxide Q22. The value of RQ for protein is

(A) One

(B) More than one

(C) Less than one

(D) Infinite

Q23. The value of RQ at compensation point is

(A) Unity

(B) Two

(C)> 1

(D) Zero

Q24. When the evolution of CO2 is more than

the intake of O2, the respired substrate

should be

(A) Fatty acid

(B)organic acid

(C) Glucose

(D) Polysaccharides

Q25. Which of the following ETS complex is inhibited by cyanide –

(A)Succinate dehydrogenase

(B)ATP synthetase

(C)cytochrome oxidase

(D)cytochrome b-c1 complex

Q26. The number of ATP molecules produced from one Krebs’ cycle are

(A) 15

(B) 36

(C) 38

28

(D)12

Q27. Which is first member of Krebs’-cycle is

(A) Malic acid

(B)Fumaric acid

(C) – ketoglutaric acid

(D)Oxalo acetic acid

Q28. Match Column - I with Column - II and select the correct option from the codes given below.

Column I Column II

A. Fats made

of three

fatty-acid

I Glycogen chains

attached to

glycerol

B. Glycolysis

metabolite

made

II Glyceraldehyde

from glycerol

C. Storage

form of

glucose

III Triglycerides

D. Result of

running

reactions

IV Glucose of

glycolysis in

reverse

(A) A-(iv), B-(ii), C-(i), D-(iii)

(B) A-(iii), B-(ii), C-(i), D-(iv)

(C) A-(iv), B-(iii), C-(i), D-(ii)

(D) A-(i), B-(ii), C-(iii), D-(iv)

Q29. Match Column-I with Column-II and select the correct option from the codes given below.

Column I Column II

A. TCA cycle I Inner

mitochondrial

membrane

B. F0 – F1

particles

II Hans Krebs

C. End product of

glycolysis

III Oxidative

Decarboxylation

D. Pyruvatedehyd

rogenase

IV Pyruvic acid

(A) A-(ii), B-(i), C-(iv), D-(iii)

(B) A-(i), B-(ii), C-(iv), D-(iii)

(C) A-(ii), B-(iii), C-(iv), D-(i)

(D) A-(iii), B-(ii), C-(i), D-(iv)

Q30. Match Column - I with Column - II and select the correct option from the codes given below.

Column I Column II

A. R.Q I Chemiosmotic

ATP

synthesis

B. Mitchel II Muscle fatigue

C. Cytochrome III Inner

mitochondrial

membrane

D. Lactic acid IV Alcoholic

fermentation

E. Yeast V Respirometer

(A) A-(v), B-(i), C-(iii), D-(ii), E-(iv

(B) A-(v), B-(i), C-(iii), D-(iv), E-(ii)

(C) A-(i), B-(v), C-(ii), D-(iii), E-(iv)

(D) A-(v), B-(ii), C-(iv), D-(iii), E-(i)

29

ANSWER KEY

EXERCISE - 1

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

C A C A C B D D D C C C C C B B C C A A

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

C B B C D D D D C D D A B C A A C B D A

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

D A B D C A B A D B A D D B A C B C D B

61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

D B D C B D C D C A D A A C B D B B A D

81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100

B B A D B C B A C A A D C B A A C C A D

101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120

C B C B C B B D C A D A A C C B A D A D

121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140

D C B D B C C B B A C B D B B B A D C A

141 142 143 144

D B D A

Exercise – 2(PYQ)

1 2 3 4 5 6 7 8 9 10 D B A D C D A B A A 11 12 13 14 15 16 17 18 19 20 C D B A D D B D B D 21 22 D D

SKILL BOOSTER – 1

1 2 3 4 5 6 7 8 9 10 B A D B B A A C D D 11 12 13 14 15 16 17 18 19 20 C A C C C B C D D B 21 22 23 24 25 26 27 28 29 30 C A A B C A C B A B

30

SKILL BOOSTER –2

1 2 3 4 5 6 7 8 9 10 C C C C B C C A B C 11 12 13 14 15 16 17 18 19 20 A C D B C D C C D C 21 22 23 24 25 26 27 28 29 30 C C A A C D B C B B

SKILL BOOSTER - 3

1 2 3 4 5 6 7 8 9 10 B C C A B B C D A A 11 12 13 14 15 16 17 18 19 20 A A B C B B D D D B 21 22 23 24 25 26 27 28 29 30 A C A B C D D B A A