Match Column-I with Column- II. 
Choose the correct answer from the options given below.
The product(s) of reaction catalyzed by nitrogenase in root nodules of leguminous plant is / are. 
Nitrogenase enzyme are responsible for the reduction of N2 to ammonia the product of reaction catalized by nitrogenase in root nodule of leguminous plants are ammonia and hydrogen
A thiobacillus is a group of bacteria helpful in carrying out 
Denitrification is the process opposite to nitrogen fixation in which nitrates (NO-3) get converted into N2 gas by bacteria Pseudomonas denitrificans and Thiobacillus denitrificans.
In the process of denitrification, nitrates are reduced to gaseous compounds of nitrogen. Common bacteria causing denitrification of soil are Thiobacillus denitrificans, Pseudomous denitrificans, etc.
Which of the following elements is responsible for maintaining turgor in cells? 
Potassium helps in the maintenance of cell turgidity and opening and closing of stomata.
In which of the following all three are macronutrients? 
From the given options, Option b has a better answer with macronutrients - Nitrogen, potassium and Phosphorus.
All other options have only micronutrients and thus 'b' turns the correct answer.
The primary macronutrients: nitrogen (N), phosphorus (P), potassium (K)
The three secondary macronutrients: calcium (Ca), sulfur (S), magnesium (Mg) the micronutrients/trace minerals: boron (B), chlorine (Cl), manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), molybdenum (Mo), nickel (Ni).
In relatively large amounts, the soil supplies nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur; these are often called the macronutrients. In relatively small amounts, the soil supplies iron, manganese, boron, molybdenum, copper, zinc, chlorine, and cobalt, the so-called micronutrients. Nutrients must be available not only in sufficient amounts but also in appropriate ratios. So, the correct answer is option b.
Minerals known to be required in large amounts for plant growth include: 
Phosphorus, potassium, sulphur and calcium play an important role in plants growth. These minerals are required in large amount.
Phosphorus is required for all phosphorylation reactions and constitution of cell membrane, nucleic acids and some proteins.
Potassium is related to protein synthesis, closing and opening of stomata and activation of enzyme.
Calcium regulates metabolic activities, function of cell membrane and stabilizes the structure of chromosomes.
Sulphur is the main constituent of the amino acids, cystine and methionine, coenzymes and vitamins.
Deficiency symptoms of nitrogen and potassium are visible first in: 
The parts of the plants that show the deficiency symptoms also depend on the mobility of the element in the plant. For elements that are actively mobilised within the plants and exported to young developing tissues, the deficiency symptoms tend to appear first in the older tissues.
For example, nitrogen, potassium and magnesium are visible first in the senescent leaves.
Which of the following elements is a constituent of biotin? [NEET Kar. 2013]
Biotin, also known as vitamin H, is a water-soluble B-vitamin. It is a coenzyme for carboxylase enzymes, involved in the synthesis of fatty acids, isoleucine, valine and in gluconeogenesis. Sulphur is a constituent of biotin.
Which two distinct microbial processes are responsible for the release of fixed nitrogen as dinitrogen gas (N2) to the atmosphere? [NEET Kar. 2013]
In the global nitrogen cycle, bacterial denitrification is recognised as important process that converts fixed nitrogen to atmospheric nitrogen gas, N2. In marine nitrogen cycle, anaerobic oxidation of ammonium coupled to nitrate reduction, contributes substantially to N2–production in marine sediments.
The first stable product of fixation of atmospheric nitrogen in leguminous plants is : [NEET 2013] (a) (b) (c)
Ammonia is first stable compound produce in fixation of atmospheric nitrogen in leguminous plant. A molecule of nitrogen is change into two molecules of ammonia. It requires 16 ATP, a source of electron donor ferredoxin, hydrogen donor NADPH or FMNH2 and dinitrogenase enzyme.
For its action, nitrogenase requires [2012M]
Nitrogenases are enzymes used by some organisms to fix atmospheric nitrogen gas. It is the only known family of enzymes that accomplish this process. Nitrogenase requires high input of energy & anaerobic condition.
Read the following four statements (A-D).
(A) Both, photophosphorylation and oxidative phosphorylation involve the uphill transport of protons across the membrane.
(B) In dicot stems, a new cambium originates from cells of pericycle at the time of secondary growth.
(C) Stamens in flowers of Gloriosa and Petunia are polyandrous.
(D) Symbiotic nitrogen-fixers occur in the free-living state also in soil.
Q. How many of the above statements are correct? [2012M]
Symbiotic nitrogen-fixing bacteria and Cyanobacteria are found in association to plant. The most common symbiotic bacteria is Rhizobium.
In dicot stem, the cambium present between xylem and phloem in vascular bundles is called fascicular or intrafascicular cambium. Besides this some cells of medullary rays also become meristematic and called interfascicular cambium.
For its activity, carboxypeptidase requires [2012M]
Carboxypeptidase is an exopeptidase enzyme secreted by the pancreas that acts only on the peptide linkage of a terminal amino acid containing a free carboxyl group. Zinc is a cofactor for carboxypeptidase. In digestion carboxypeptidase, requires zinc for its protein degrading action.
Which one of the following is correctly matched ? 
Active transport needs energy for the transport of molecules in the cells. Translocation occurs through the plasmodesmata. Bakanae disease affect the rice plant.
Correct option (c) Potassium - Readily immobilisation
Explanation : Active transport of nutrients require ATP Symplast includes translocation through plasmodesmata. Bakane disease of rice was found by Hori (1918) to be caused due to Gibberella fujikuroi. None of the options is correct Option (c) may be correct if statement be read as "Potassium readily moibilisation" instead of "potassium readily immobilisation.
Best defined function of Manganese in green plants is : 
The best defined function of manganese is in the splitting of water to liberate oxygen during photosynthesis. It is absorbed in the form of manganous ions (Mn2+). It activates many enzymes involved in photosynthesis, respiration and nitrogen metabolism.
Which one of the following is essential for photolysis of water ? [2011M]
Photolysis is catalysed by the proteinbound inorganic complex containing manganese ions (oxygen evolving complex) of photosystem II.
Which one of the following is not an essential mineral element for plants while the remaining three are? [2011M]
Cadmium is not an essential element for
plants. Phosphorus is macronutrient and iron and manganese are micronutrients for plants.
The function of leg haemoglobin in the root nodules of legumes is : 
Leghaemoglobin is the haemoglobin like red pigments found in root nodules of legumes and reported to function as an oxygen-carrying pigment in symbiotic nitrogen fixation.
Nitrifying bacteria : 
The nitrifying bacteria bring about transformations of ammonia to nitrite and of nitrite to nitrate.
Which one of the following elements in plants is not remobilised? 
Calcium is not remobilized from the leaves to the fruits, like potassium, phosphorus and sulphur. It occurs abundantly in a non-exchangeable form such as anorthite (CaAl2Si2O8).
A prokaryotic autotrophic nitrogen fixing symboint is found in : 
A prokaryotic autotrophic nitrogen fixing symbiont is found in Cycas.
One of the free -living, anaerobic nitrogen - fixer is: 
Rhodospirillum is a free-living, anaerobic nitrogen fixer bacteria. It can synthesize its food in presence of light under anaerobic condition.
Beijernickia and Azotobacter are free living aerobic nitrogen fixing bacteria. Rhizobium is a symbiotic nitrogen fixing bacteria.
Which one of the following is not a micronutrient? 
Magnesium is a macronutrient. Micronutrients are essential elements that are required by plants in small amount. They include Fe, Cu, B, Mo, Mn, Cl, and Ni. Macronutrients, on the other hand, are those essential elements that are required by plants in larger amount. The examples include C, H, O, N, S, P, K, Ca and Mg.
An element playing important role in nitrogen fixation is : 
Molybdenum is a micronutrient that plays an important role in nitrogen fixation. It is a part of nitrate reductase enzyme that helps in nitrogen fixation.
Which of the following is a symbiotic nitroger fixer?
Frankia is symbiotic nitrogen fixer in root nodules of several non-legume plants like Casurina and Alnus.
Which one of the following pairs is wrongly matched? 
Alcohol and nitrogenase pair is wrongly matched. Ethanol produces alcohol.
Manganese is required in: 
Manganese is essential for many plant functions. Some of them are:
Nitrogen fixation in root nodules of Alnus is brought about by: 
Nitrogen fixation in root nodules of Alnus is brought about by Frankia. Frankia is a symbiotic nitrogen fixing bacteria in root nodules of several nonlegune plants like Casuarina (Australian Pine), Myrica and Alnus (Alder).
Which one of the following elements is not an essential micronutrient for plant growth? 
Essential micro elements are Fe, Mn, Zn, B, Cu, Mo and essential macronutrionts are C,H, N, P, S, Ca, K, Mg.
Which one of the following is wrong statement
Phosphorus: Phosphorus is absorbed by the plants from soil in the form of phosphate ions (either as H PO 2 4 − or HPO4 2− ). Phosphorus is a constituent of cell membranes, certain proteins, all nucleic acids and nucleotides, and is required for all phosphorylation reactions.