Which one of the following is not a nitrogen-fixing organism?
1. Anabaena
2. Nostoc
3. Azotobacter
4. Pseudomonas
How many ATP molecules are required to biologically fix one molecule of nitrogen into two molecules of ammonia?
1. 4
2. 8
3. 12
4. 16
When the plants are grown in magnesium deficient but urea rich soil, the symptoms expressed are:
1. yellowish leaves
2. colourless petiole
3. dark green leaves
4. shoot apex die.
Select the mismatch.
(1) Frankia Alnus
(2) Rhodospirillium Mycorrhiza
(3) Anabaena Nitrogen fixer
(4) Rhizobium Alfa-fa
Which is essential for the growth of root tip?
(1) Zn
(2) Fe
(3) Ca
(4) Mn
The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements involved in this reaction?
1. Manganese and chlorine
2. Manganese and potassium
3. Manganese and molybdenum
4. Magnesium and chlorine
Minerals known to be required in large amounts for plant growth include
1. Phosphorus, potassium, sulphur, calcium
2. calcium, magnesium, manganese, copper
3. potassium, phosphorus, selenium, boron
4. magnesium, sulphur, iron, zinc
Deficiency symptoms of nitrogen and potassium are visible first in
1. senescent leaves
2. young leaves
3. roots
4. buds
The most abundant intracellular cation is
1. Na+
2. Ca2+
3. H+
4. K+
Best defined function of manganese in green plants is
1. photolysis of water
2. Calvin cycle
3. nitrogen fixation
4. water absorption