In photorespiration, glycolate is converted into serine and carbon dioxide in:
In the C4 pathway, which of the following molecules combines with carbon dioxide?
1. glyceraldehyde phosphate
2. ribulose biphosphate
3. phosphoenol pyruvic acid
4. citric acid
An action spectrum of photosynthesis was first described by:
1. Jan Ingenhousz
2. Julius von Sachs
3. T.W. Engelmann
4. Cornelius van Niel
All the following regarding the role of xanthophylls and carotenoids in photosynthesis are correct except:
1. They act as accessory pigments
2. Their peak absorption is in blue and red regions of VIBGYOR
3. They enable a wider range of wavelength of incoming light to be utilized for photosynthesis
4. They protect chlorophyll a form of photo-oxidation.
Which of the following are special features of the C4 plants?
I. They have a special type of leaf anatomy.
II. They tolerate higher temperatures and show a response to high light intensities.
III. They lack photorespiration and have greater productivity of biomass.
1. Only I and II
2. Only I and III
3. Only II and III
4. I, II and III
Compared to retinal, chlorophyll can be described as a pigment that has a
1. narrow absorption range but high efficiency
2. narrow apsorption range but low efficiency
3. wide absorption range but high effeciency
4. wide absorption range but low efficiency
Consider the situation where photosynthesis is going on at a steady pace in a typical experiment with a light on, and carbon dioxide is being combined with ribulose-bisphosphate (RuBP) to produce 3-phosphoglycerate (3PG). Then suddenly the source of carbon dioxide is eliminated. What changes in the concentrations of 3PG and RuBP would occur?
1. 3PG levels rise, RuBP levels fall.
2. 3PG levels fall, RuBP levels rise.
3. 3PG levels rise, RuBP levels rise.
4. 3PG levels fall, RuBP levels fall.
Identify the statement that is true for C4 plants but not for C3 plants?
1. Initially fix carbon dioxide in mesophyll cells as 4-carbon long compounds.
2. Initially fix carbon dioxide in bundle sheath cells as 3-carbon long compounds.
3. Initially fix carbon dioxide in mesophyll cells as 3-carbon long compounds.
4. Initially fix carbon dioxide in bundle sheath cells as 4-carbon long compounds.
Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using the following options.
1. Both process can happen together because the diffusion coefficient of water and CO2 is different.
2. The above processes happen only during night time
3. One process occurs during the day time and the other night
4. Both processes cannot happen simultaneously
The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements involved in this reaction?
1. Manganese and chlorine
2. Manganese and potassium
3. Manganese and molybdenum
4. Magnesium and chlorine
C4 -plants are more efficient in photosynthesis than C3 -plants due to
1. higher leaf area
2. presence of larger number of chloroplasts in the leaf cells.
3. presence of thin cuticle
4. lower rate of photorespiration
Cyclic-photophosphorylation results in the formation of
2. ATP and NADPH
3. ATP, NADPH and O2
Electrons from excited chlorophyll molecule of photosystem-II are accepted first by
Carbohydrates are commonly found as starch in plant storage organs. Which of the
following five properties of starch (A-E) make it useful as a storage material?
(A) Easily translocated
(B) Chemically non-reactive
(C) Easily digested by animals
(D) Osmotically inactive
(E) Synthesized during photosynthesis
The useful properties are
1. (B) and (C)
2. (B) and (D)
3. (A), (C) and (E)
4. (A) and (E)
Which of the following statements about phytochrome is true?
1. Pr absorbs yellow light and becomes Pfr
2. Pr absorbs red light and becomes Pfr
3. Pfr absorbs red light and becomes Pr
4. Pfr absorbs yellow light and becomes Pr .
Read the following statements:
(a) F part of ATPase is associated with breakdown of proton gradient.
(b) A H-carrier contributes in creation of proton gradient.
(c) Movement of electrons in ETS is coupled to pumping of protons into the lumen.
(d) Formation of NADPH + H is related with the creation of proton gradient.
How many of the above statements are correct?
Moll's half leaf experiment was done to show _____ was required for photosynthesis.
RuBisCo in C plants shows minimum oxygenase activity due to
1. Abundance of RuBisCO
2. Formation of C acid
3. Decarboxylation of C acid
4. Cylclic photophosphorylation
Which of the following would rarely be a limiting factor for photosynthesis?
3. Carbon dioxide
Law of limiting factor was given in
A : Dark reactions of photosynthesis are temperature controlled processes.
R : Most of the reactions are enzymatic in nature.
In photosystem-I, the first electron acceptor is
4. An iron-sulphur protein
During photorespiration, the oxygen consuming reaction(s) occur in
1. Stroma of chloroplasts and mitochondria
2. Stroma of chloroplasts and peroxisomes
3. Grana of chloroplasts and peroxisomes
4. Stroma of chloroplasts
Which one of the following organisms is correctly matched with its three characteristics ?
1. Pea : C3 pathway, Endospermic seed, Vexillary aestivation
2. Tomato: Twisted aestivation, Axile placentation, Berry
3. Onion : Bulb, Imbricate aestivation, Axile placentation
4. Maize : C3 pathway, Closed vascular bundles, Scutellum
A : Most of the photosynthesis takes place in the blue and red region of spectrum.
R : Action spectrum shows the amount of energyy of different wavelength of light absorbed by pigment.
How many components listed below are part of cyclic ETS ?
Curve showing the effectiveness of different wavelength of light in photosynthesis was first given by Engelmann using all, except
1. Filamentous green alga Cladophora
2. Unicellular green alga Chlorella
3. Suspension of aerobic bacteria
4. Prism to split the light in its components
Which among the following is not a step in Calvin cycle ?
Choose the correct sequence of steps involved in C4 cycle
1. fixation Regeneration Transport
2. fixation Recarboxylation Decarboxylation
3. Transport Regeneration fixation
4. fixation Transport Decarboxylation
Choose the correct labelling for given figure
1. D-saturation point, E-Maximum photosynthesis
2. A- Achieved at high light intensity
3. D-10% of total sunlight, E-compensation point
4. A- Light saturation at 10% of total sunlight
Essentiality of in photosynthesis can be demonstrated using
1. Moll's half leaf experiment
2. Ganong screen
3. Inverted funnel experiment
4. KOH solution
With reference to factors affecting the rate of photosynthesis, which of the following statement is not correct ?
1. Light saturation for fixation occurs at 10 % of full sunlight
2. Increasing atmosphere concentration upto 0.05% can enhance fixation rate
3. plants responds to higher temperatures with enhanced photosynthesis while plants have much lower temperature optimum
4. Tomato is a greenhouse crop which can be grown in - enriched atmosphere for higher yield
ATP synthesis in chloroplast and mitochondria is due to proton gradient across the membrane. Select correct statement w.r.t ATP formation in chloroplast
(a) Proton accumulated in lumen of thylakoid
(b) Splitting of water occurs on inner side of membrane
(c) Proton accumulates in stroma side of chloroplast
(d) NADP reductase is located on stroma side of membrane
1. Only (a) and (b) are correct
2. Only (b) and (c) are correct
3. Only (c) and (d) are correct
4. (a),(b) and (d) are correct
A : Assimilatory power in photosynthesis is generated in ETS occuring in thylakoid membrane
R : They are needed for CO2 reduction and RuBP regeneration
Read the following four statements a,b,c and d and select the right option having both correct statements
a. Z scheme of light reaction takes place in presence of PSI only
b. Only PS I is functional in cyclic photophoshphorylation
c. Cyclic photophosphorylation results into synthesis of ATP and NADPH2
d. Stroma lamellae lack PS II as well as NADP
1. B and D
2. A and B
3. B and C
4. C and D
Study the pathway given below :
In which of the following options correct words for all the three blanks A,B and C are indicated ?
Emerson's enhancement effect and Red drop have been instrumental in the disovery of
1. Oxidatiove phosphorylation
2. Photophosphorylation and non-cyclic electron transport
3. Two photosystems operating simultaneously
4. Photophosphorylation and cyclic electron transport
A : Light harvesting complexes (LHC) on thylakoid membrane broaden the range of light absorption.
R : They transfer e- to reaction centre
In the chloroplast, the stroma lamellae lack the
1. PS I, NADP reductase
2. PS II, PS I
3. NADP reductase enzyme, P700
4. NADP reductase, PS II
How many electrons, protons and photons are involved in the lysis of water to evolve one molecule of oxygen ?
1. 4e-, 4H+ & 4 photons
2. 4e-, 4H+ & 8 photons
3. 2e-, 2H+ & 8 photons
4. 2e-, 2H+ & 4 photons