Which of the following elements helps in maintaining the structure of ribosomes?

1. Magnesium

2. Zinc

3. Copper

4. Molybdenum

The most abundant intracellular cation is :
1. Ca²⁺
2. H⁺
3. K⁺
4. Na⁺

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
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 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 alongwith 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 synthesis of chlorophyll