Light recation

Q.

The assimilatory power in photosynthesis is

1. CO₂

2. ATP

3. NADPH

4. ATP and NADPH₂

Q.

What happens when ${\mathrm{XeF}}_6$ undergo complete hydrolysis?

Q.

Which of the following sequences correctly represents the flow of electrons during photosynthesis?

1. NADPH → O2 → CO2

2. H2O → NADPH → Calvin cycle

3. NADPH → chlorophyll → Calvin cycle

4. H2O → photosystem I → photosystem II

Q.

The first step for initiation of photosynthesis will be

1. Formation of ATP

2. Ionization of water

3. The excitement of an electron of chlorophyll by a photon of light

4. Joining of a 3-carbon atom to form glucose

Q. Which one of the following is not true about the light reactions of photosynthesis?

1. NADPH is not produced in cyclic electron transport in light reaction
2. Light energy provides energy for the photolysis of water through excitation of the reaction centre of PS-II
3. Reactions of the two photosystems are needed for the reduction of NADP
4. P680 and P700 are the reaction centers of PS-I and PS-II, respectively
5. The flow of electrons from water to NADP in noncyclic electron transport produces one ATP

Q. Plants adapted to low light intensity have:

1. More extended root system
2. Higher rate of $C{O}_2$ fixation than the sun plants
3. Leaves modified to spines
4. Larger photosynthetic unit size than the sun plants

Q.

The oxygen that is released as O${}_2$ during photosynthesis came from _____________ molecules.

1. carbon dioxide

2. water

3. glucose

4. chlorophyll

Q.

During what stage of photosynthesis is O${}_2$ produced?

1. cyclic photophosphorylation

2. carbon fixation

3. the light-dependent reactions involving photosystems I and II

4. the Krebs cycle

Q. Identify the reaction series. It takes place in stroma or cytoplasm, using ATP and NADPH from photosynthesis with $C{O}_2$ and $H_{2}O$ to produce carbohydrate.

1. Calvin cycle

2. Glycolysis

3. Hatch and slack pathway

4. Kreb cycle

Q.

The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements is involved in this reaction?

1. Manganese and Chlorine

2. Manganese and Potassium

3. Magnesium and Molybdenum

4. Magnesium and Chlorine

Q. Which of the following statements is true with regard to the light reaction of photosynthesis?

1. Photo systems – I and II are involved in Z – scheme.
2. In PS – I, the reaction centre chlorophyll –a has an absorption maxima at 680 nm and is called p680
3. In PS – II reaction centre, chlorophyll – a has an absorption peak of 700 nm, hence called p700
4. The splitting of water molecule is associated with PS – II

Q. Photochemical reactions in the chloroplast are directly involved in

1. Fixation of carbon dioxide
2. Synthesis of glucose and starch
3. Photolysis of water and phosphorylation of ADP to ATP
4. Formation of phosphoglyceric acid

Q. Light energy in photosynthesis is utilised in

1. ADP converted into ATP
2. H₂O converted into H₂
3. ATD converted into ADP
4. None of the above.

Q. Which of the following statements is true with regard to light reaction of photosynthetic mechanism in plants?

1. $O_2$ is evolved during cyclic photophosphorylation
2. Chlorophyll-a occurs with peak absorption at 680 nm in photosystem -I and at 700 nm in photosystem - II
3. Magnesium and sodium ions are associated with photolysis of water molecules
4. Photosystem - I and II are both involved in non-cyclic photophosphorylation
5. Both ATP and $NADP{H}_2$ are formed during cyclic photophosphorylation

Q.

ATP synthesis during light reaction is

1. Oxidative phosphorylation

2. Photophosphorylation

3. Photolysis

4. Phosphorylation

Q. A herbicide that blocks electron transport from PS-II to PS-I by inhibiting electron flow between PSII and plastoquinone is______

1. Paraquat
2. DCPIP
3. None of these
4. DCMU

Q. The first step in photosynthesis is the

1. Joining of 3-carbon atom to form glucose
2. Formation of ATP
3. Ionization of water
4. Excitement of an electron of chlorophyll by a photon of light
   

Q. Assimilatory power that is produced in the light reaction and used in Blackman’s reaction referes to the

1. Splitting of water
2. Disintegration of plastids
3. Reduction of $C{O}_2$
4. Generation of ATP and $NADP{H}_2$