Electrons from excited chlorophyll molecule of photosystem-II are accepted first by

1. cytochrome-b

2. cytochrome-f

3. quinone

4. ferredoxin

In the leaves of C₄ -plants malic acid synthesis during CO₂ fixation occurs in 

(1) epidermal cells

(2) mesophyll cells

(3) bundle sheath

(4) guard cells

The wavelength of light abosorbed by P_r form of phytochrome is :

(1) 640 nm

(2) 680 nm

(3) 720 nm

(4) 620 nm

In photosystem-I, the first electron acceptor is :

(1) ferredoxin

(2) cytochrome

(3) plastocyanin

(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

Photorespiration is favoured by

(1) high O₂ and low CO₂ concentration

(2) low O₂ and high CO₂ concentration

(3) low light intensity

(4) low temperature.

The C₄ plants grow very efficiently in warm climates because they

(1) consume fewer ATP molecules for glucose synthesis

(2) minimize photorespiratory losses

(3) have more efficient chloroplasts

(3) contain enzymes which are not inactivated at high temperatures.

Following is needed in the ionic form during non-cyclic photophosphorylation but not during cyclic photophosphorylations in higher plants. 

(1) copper

(2) iron

(3) manganese

(4) zinc

Production of NADPH in a chloroplast takes place during

1. cyclic photophosphorylation

2. non-cyclic photophosphorylation

3. series photophosphorylation

4. substrate level photophosphorylation.

The photoautotrophic organisms that do not split water to obtain reducing power are 

(1) purple bacteria 

(2) cyanobacteria

(3) green plants

(4) none of these