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