Q. No.The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements are involved in this reaction?
1. Manganese and chlorine
2. Manganese and potassium
3. Magnesium and molybdenum
4. Magnesium and chlorine
1. Magnesium
2. Calcium
3. Phosphorus
4. Sulphur
Best defined function of manganese in green plants is :
1. Photolysis of water
2. Calvin cycle
3. Nitrogen fixation
4. Water absorption
Which one of the following is a wrong statement?
| 1. | Anabaena and Nostoc are capable of fixing nitrogen in a free-living state also |
| 2. | Root nodule-forming nitrogen fixers live as aerobes under free-living conditions |
| 3. | Phosphorus is a constituent of cell membranes, certain nucleic acids, and all proteins |
| 4. | Nitrosomonas and Nitrobacter are chemoautotrophs |
Which one of the following is essential for the photolysis of water?
1. Boron
2. Manganese
3. Zinc
4. Copper
An element playing important role in nitrogen fixation is:
1. molybdenum
2. copper
3. manganese
4. zinc
Manganese is required in:
1. nucleic acid synthesis
2. plant cell wall formation
3. photolysis of water during photosynthesis
4. chlorophyll synthesis
A plant requires magnesium for:
1. holding cells together
2. protein synthesis
3. chlorophyll synthesis
4. cell wall development
Farmers in a particular region were concerned that pre-mature yellowing of leaves of a pulse crop might cause a decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield?
| 1. | Frequent irrigation of the crop |
| 2. | Treatment of the paints with cytokinins along with a small dose of nitrogenous fertilizer |
| 3. | Removal of all yellow leaves and spraying the remaining green leaves with 2,4,5-trichlorophenoxy acetic acid |
| 4. | Application of iron and magnesium to promote the synthesis of chlorophyll |
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