Emerson's Effect

Q. Red drop effect results in

1. drop in quantum yield
2. drop in photosynthetic yield
3. drop in oxygen yield
4. drop in organic yield

Q. Antenna pigment molecules transfer the light energy to the reaction center of light-harvesting complex. This phenomenon is called as:-

1. Shifting of light
2. Resonance transfer
3. Inductive resonance
4. Charge separation

Q. Which pigment system is inactivated in red drop?

1. PS-I and PS -II
2. PS-II
3. None
4. PS-I

Q. The rate of photosynthesis is maximum in which colour of light?

1. In green light
2. In red light
3. In yellow light
4. In purple light

Q. Identify A, B, C, D and E in the given flow chart showing Z–scheme of light reaction.

1. 
   $A–P_{700},B–H^{+}$ acceptor, $C–e^{–}$ acceptor, $D–P_{680},E–NAD{P}^{+}$
2. 
   A–Photo–system I, $B–e^{–}$ acceptor, $C–e^{–}$transport system, D–Photo system II, E–NADPH
3. A–Photo–system II, $B–H^{+}$ acceptor, C–e–acceptor, $D–P_{700}$, E–NADPH
4. A–Photo–system II, $B–e^{–}$ acceptor, $C–e^{–}$ transport system, D–Photo–system I, E–NADPH

Q. Red drop discovered by Emerson is due to disruption of photochemical activity of

Q. Red drop effect results in

1. drop in quantum yield
2. drop in photosynthetic yield
3. drop in oxygen yield
4. drop in organic yield

Q. The two pigment system theory of photosynthesis was proposed by

1. Hill
2. Arnon
3. Ruben and Kamen
4. Emerson

Q. Emerson effect is related to

1. Photosynthesis
2. Respiration
3. Transpiration
4. Absorption of water

Q. Cyclic photophosphorylation will not occur without:

1. H${}_2$O
2. Photosystem-II
3. Chlorophyll a
4. NADP${}^{+}$

Q. Red drop phenomenon and Emerson’s enhancement effect have been helpful in the discovery of

1. photophosphorylation and non-cyclic electron transport
2. two photosystems operating simultaneously
3. source of oxygen released during photosynthesis
4. oxidative phosphorylation

Q. Red drop phenomenon affects

1. PS I.
2. PS II.
3. Accessory pigments.
4. Chlorophyll.

Q. Which of the following is the first step in photosynthetic process?

1. Formation of a 3-carbon compound PGA
2. Formation of ATP
3. Photoionization of water
4. Photo excitation of an electron of chl-a, by a photon of light

Q. Discovery of Emerson effect showed the existence of

1. Photophosphorylation
2. Photorespiration
3. Two distinct photochemical reactions
4. Light and dark reaction in photosynthesis

Q. The rate of photosynthesis decreases if the wavelength of visible light exceeds 680 nm. This was shown by which scientist and what is it's reason?

1. Black man - Law of limiting factor
2. Calvin and Benson - Photooxidation
3. Emerson and Arnold - Red drop
4. Ruben and Kamen - Photolysis

Q. Who amongst the following, first observed photosynthesis in plants?

1. Melvin Calvin
2. Darwin
3. Arnon
4. R. Hill

Q.

Emerson's enhancement effect leads to the conclusion that

1. Two pigment systems are involved in photosynthesis and they absorb light of different wavelengths.

2. Two wavelengths together increase the quantum yield of photosynthesis.

3. The pigment systems have a reaction centre surrounded by light harvesting accessory pigment molecules

4. None of the above

Q. Two pigment systems in photosynthesis was proposed by

1. Emerson
2. Calvin
3. Ruben
4. D.I. Arnon.

Q. Red drop discovered by Emerson is due to disruption of photochemical activity of

1. Carotenoids.
2. PS I.
3. PS II.
4. Both B and C.

Q. Emerson effect explain the phenomenon of

1. Absorption of water by roots
2. Transpiration
3. Photosynthesis
4. Respiration

Q. Red drop occurs in wavelength of

1. 492 nm
2. 535 nm
3. 586 nm
4. 680 nm.

Q.

Emerson's enhancement effect leads to the conclusion that

1. Two pigment systems are involved in photosynthesis and they absorb light of different wavelengths.

2. None of the above

3. The pigment systems have a reaction centre surrounded by light harvesting accessory pigment molecules

4. Two wavelengths together increase the quantum yield of photosynthesis.

Q. Which of the following sequences correctly portrays the flow of electrons during photosynthesis?

1. $H_{2}O$ $\to$ NADPH $\to$ Calvin cycle
2. NADPH $\to$ chlorophyll $\to$ Calvin cycle
3. $H_{2}O$ $\to$ photosystem-I $\to$ photosystem-II
4. NADPH $\to$ electron transport chain $\to$ $O_2$

Q. The two pigment system theory of photosynthesis was proposed by

1. Hill
2. Arnon
3. Ruben and Kamen
4. Emerson

Q. Which pigment system is inactivated in red drop?

1. PS-I and PS -II
2. PS-I
3. PS-II
4. None

Q.

Colour of a star gives us the idea about its

1. Weight

2. Distance

3. Size

4. Temperature

Q. Who discovered the phenomenon of red drop? In which part of the visible spectrum does this phenomenon occur?

Q. Red drop phenomenon and Emerson’s enhancement effect have been helpful in the discovery of

1. oxidative phosphorylation
2. photophosphorylation and non-cyclic electron transport
3. source of oxygen released during photosynthesis
4. two photosystems operating simultaneously

Q. Red drop occurs in wavelength of

1. 492 nm
2. 535 nm
3. 586 nm
4. 680 nm

Q. Emerson’s enhancement effect and Red drop have been instrumental in the discovery of:

1. Photophosphorylation and non – cyclic electron transport
2. Two photosystems operating simultaneously
3. Photophosphorylation and cyclic electron transport
4. Oxidative phosphorylation