Enzyme first used for nitrogen fixation:
1.  Nitrogenase
2.  Nitroreductase
3.  Transferase
4.  Transaminase

Passive absorption of minerals depends on:
1.  Temperature
2.  Temperature and metabolic inhibitor
3.  Metabolic inhibitor
4.  Humidity

Cytochrome is:
1.  Metallo flavo protein
2.  Fe containing porphyrin pigment
3.  Glycoprotein
4.  Lipid

Which aquatic fern performs nitrogen fixation:
1.  Azolla
2.  Nostoc
3.  Salvia
4.  Salvinia

Roots of which plant contains a pink pigment that has an affinity for oxygen:
1.  Carrot
2.  Soyabean
3.  Mustard
4.  Radish

What is the best pH of the soil for the cultivation of plants:
1.  3.4 – 5.4
2.  6.5 – 7.5
3.  4.5 – 8.5
4.  5.5 – 6.5

Grey spots of oat are caused by deficiency of:

1. Cu

2. Zn

3. Mn

4. Fe

Boron in green plants assists in:
1. Activation of enzymes
2. Acting of enzyme cofactor
3. Photosynthesis
4. Sugar transport

In which one of the following nitrogen is not a constituent:

1. Idioblast

2. Bacteriochlorophyll

3. Invertase

4. Pepsin

Plants deficient in the element zinc show its effect on the biosynthesis of which plant growth hormone: