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
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 |
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 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
Sulphur is an important nutrient for optimum growth and productivity in:
1. pulse crops
2. cereals
3. fibre crops
4. oilseed crops
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