Test: Mineral Nutrition - 2 (Old NCERT) - ACT MCQ

The technique of growing plants in a nutrient solution is known as hydroponics.

Zn²⁺ is an activator of alcohol dehydrogenase and Mo of nitrogenase during nitrogen metabolism.

The correct option is Option A.

Macroelements (Macronutrients) are those essential elements which are present in easily detectable quantities, 1-10 mg per gram of dry matter. Macroelements are usually involved in the synthesis of organic molecules and development of osmotic potential. They are nine in number — C, H, O, N, P, K, S, Mg and Ca.

The nutrient required in larger quantity is called macronutrients. Those essential elements which occur in 1-10mg/g quantity is called macronutrients.
 

pH of a solution is depends upon hydrogen ions concentration. Influx and efflux of H+ ions inside the cell change the pH of solution present in soil.

In nitrification, ammonia is first converted to nitrites (NO₂-) and then to nitrates. During nitritation, nitrosomonas convert NH₃(ammonia) into NO2 (nitrogen dioxide). The chemical equation for this process is 

NH₃ + 1.5 O₂ --> NO₂^- + H⁺ + H₂0. 

The second part of the nitrification process is called nitration.

Aeroponics is the technique of growing plants in above ground strands provided with fine mist of normal solution. It is used to know the deficiency symptoms of minerals.

Plants obtain iron in the form of ferric ions (Fe3+). It is required in larger amounts in comparison to other micronutrients. It is an important constituent of proteins involved in the transfer of electrons like ferredoxin.

Sodium and Iodine minerals are not needed by the majority of plants but sodium and iodine minerals are very much needed by almost all animals. Sodium play important role in nervous system and iodine for synthesis thyroxine hormone.

Most of the minerals present in soil can enter plants through roots.

Decomposition of organic nitrogen of dead plants and animals into ammonia is called ammonification.Some of this ammonia volatilises and re-enters the atmosphere but most of it is converted into nitrate by soilBacteria.

Plants obtain zinc as Zn2+ ions. It activates various enzymes,especially carboxylases. It is also needed in the synthesis of auxin.If there is deficiency in zinc to plants then it leads to reduced synthesis of auxin.

It is absorbed in the form of manganous ions (Mn2+). Itactivates many enzymes involved in photosynthesis, respiration and nitrogen metabolism.

During ammonification process involve conversion of nitrate into ammonia. This process involves two steps. Second steps require electron that is donated by Ferredoxin.

Entry of ions into cells is called influx. Influx takes place actively against the concentration gradient by utilization of energy through plasmodesmata of plant cells.

N²⁻fixing bacteria, especially roots of legumes, can fix this atmospheric nitrogen into biologically usable forms. Nitrogen fixation requires a strong reducing agent and energy in the form of ATP. Nitrogen-fixation is accomplished with the help of nitrogenfixingmicrobes mainly rhizobium.

Calcium is required by meristematic and differentiating tissues. During cell division it is used in the synthesis of cell wall, particularly as calcium pectate in the middle lamella.

Micronutrients or trace elements, are needed in very small amounts(less than 10 mole Kg –1 of dry matter). These include iron, manganese, copper, molybdenum, zinc, boron, chlorine and nickel.

Rice field contains large number of nitrogen fixing algae and bacteria. In which Aulosira fertilissima is most active nitrogen fixer in the rice field.

Glomus is a kind of algae found in soil. This organism help in absorption of phosphorous form soil by plants.

Nitrogen exists as two nitrogen atoms joined by a very strong triple covalent bond (N ≡ N).

Carbon is one of the macronutrients present in the plants. It is the most abundant element found in plants. Carbon is a constiuent of organic compounds. It is one of the non-mineral element. Carbohydrates like sugars, starches and cellulose are the important organic compounds composed of carbon present in plants.

Some elements like N, S, Mo delay flowering if their concentration in plants is low.

Mineral deficiency is soil may be due to use of high yielding varieties, non-rotation of crops and leeching of minerals. Growing leguminous plants do not deplete the mineral in soil.

Elements play important role in completing life cycles of plants. Element required for germination of pollen grain is Boron.

The process of conversion of nitrogen (N2) toammonia is termed as biological nitrogen fixation.