Mineral Nutrition

Magnesium

________ is a constituent of the ring structure of chlorophyll and helps to maintain the ribosome structure.

Industrial combustions

________, forest fires, automobile exhausts and power- generating stations are also sources of atmospheric nitrogen oxides.

Rhizobia

________ multiply and colonise the surroundings of roots and get attached to epidermal and root hair cells.

ultraviolet radiation

In nature, lightning and ________ provide enough energy to convert nitrogen to nitrogen oxides (NO, NO2, N2O)

Chlorosis

________ is the loss of chlorophyll leading to yellowing in leaves.

requirement of micronutrients

The ________ is always in low amounts while their moderate decrease causes the deficiency symptoms and a moderate increase causes toxicity.

Plants

________ compete with microbes for the limited nitrogen that is available in soil.

prevalent element

Apart from carbon, hydrogen and oxygen, nitrogen is the most ________ in living organisms.

solute concentration

Along with Na+ and K+, it helps in determining the ________ and the anion cation balance in cells.

Reductive amination

________: In these processes, ammonia reacts with α- ketoglutaric acid and forms glutamic acid.

Boron

________ is required for the uptake and utilization of Ca2+, membrane functioning, pollen germination, cell elongation, cell differentiation, and carbohydrate translocation.

N2

The process of conversion of nitrogen (________) to ammonia is termed as nitrogenfixation.

Nodule formation

________ involves a sequence of multiple interactions between Rhizobium and roots of the host plant.

Sulfur

________ is present in two amino acids- cysteine and methionine and is the main constituent of several coenzymes, vitamins (thiamine, biotin, Coenzyme A), and ferredoxin.

potassium ion

It is absorbed as a(n) ________ (K+)

iron

Like ________, it is associated with certain enzymes involved in redox reactions and is reversibly oxidized from Cu+ to Cu2+.

crop yield

Since deficiency of essential minerals affect the ________, there is often a need for supplying them through fertilisers.

Phosphorus

________ is a constituent of cell membranes, certain proteins, all nucleic acids, and nucleotides, and is required for all phosphorylation reactions.

Nitrogen

________ is one of the major constituents of proteins, nucleic acids, vitamins, and hormones.

Potassium

________ plays an important role in the opening and closing of stomata.

BO3

It is absorbed as ________ 3− or B O4 7 2−.

Julius von Sachs

In 1860, ________, a prominent German botanist, demonstrated, for the first time, that plants could be grown to maturity in a defined nutrient solution in the complete absence of soil.

Soil

________ not only supplies minerals but also harbours nitrogen- fixing bacteria, other microbes, holds water, supplies air to the roots and acts as a matrix that stabilises the plant.

buds

In plants, this is required in more abundant quantities in the meristematic tissues, ________, leaves, and root tips.

microbe

The ________, Frankia, also produces nitrogen- fixing nodules on the roots of nonleguminous plants (e.g., Alnus)

physiological pH

At ________, the ammonia is protonated to form NH4 + (ammonium) ion.

Essential elements

________ can also be grouped into four broad categories on the basis of their diverse functions.

Micronutrients

________ or trace elements are needed in very small amounts (less than 10 mmole Kg- 1 of dry matter)

nodule

The ________ contains all the necessary biochemical components, such as the enzyme nitrogenase and leghaemoglobin.

Ammonia

________ is first oxidised to nitrite by the bacteria Nitrosomonas and /or Nitrococcus.

greatest amount

This is the essential nutrient element required by plants in the ________.

nitrate reductase

It is a component of several enzymes, including nitrogenase and ________ both of which participate in nitrogen metabolism.

Nitrate

________ present in the soil is also reduced to nitrogen by the process of denitrification.

Macronutrients

________ are generally present in plant tissues in large amounts (in excess of 10 mmole Kg- 1 of dry matter)

Transamination

________: It involves the transfer of amino group from one amino acid to the keto group of a keto acid.

Denitrification

________ is carried by bacteria Pseudomonas and Thiobacillus.

Fe2+

It is reversibly oxidized from ________ to Fe3+ during electron transfer.

respiration

It activates the enzymes of ________, and photosynthesis and is involved in the synthesis of DNA and RNA.

catalase enzyme

It activates the ________ and is essential for the formation of chlorophyll.

enzyme nitrogenase

The ________ is a Mo- Fe protein and catalyses the conversion of atmospheric nitrogen to ammonia, the first stable product of nitrogen fixation.

amino acids

Since amides contain more nitrogen than the ________, they are transported to other parts of the plant via xylem vessels.

deficiency symptoms

For elements that are actively mobilized within the plants and exported to young developing tissues, the ________ tend to appear first in the older tissues.

infection thread

A(n) ________ is produced carrying the bacteria into the cortex of the root, where they initiate the nodule formation in the cortex of the root.

water splitting reaction

It is essential for the ________ in photosynthesis, a reaction that leads to oxygen evolution.

Mineral salts

________ are translocated through xylem along with the ascending stream of water, which is pulled up through the plant by transpirational pull.

cell division

During ________, it is used in the synthesis of the cell walls, particularly as calcium pectate in the middle lamella.

Toxicity levels

________ for any element also vary for different plants.

overall metabolism of plants

It is essential for the ________.

mineral ion concentration

Any ________ in tissues that reduces the dry weight of tissues by about 10 percent is considered toxic.

Calcium

________ is required by meristematic and differentiating tissues.

Sulfur is present in two amino acids

cysteine and methionine and is the main constituent of several coenzymes, vitamins (thiamine, biotin, Coenzyme A), and ferredoxin

It is absorbed in the form of chloride anion (Cl

)

In the first phase, an initial rapid uptake of ions into the ‘free space or ‘outer space of cells

the apoplast, is passive

In the second phase of uptake, the ions are taken in slowly into the ‘inner space

the symplast of the cells

Such microbes are called N2

fixers

Reductive amination

In these processes, ammonia reacts with α-ketoglutaric acid and forms glutamic acid

Transamination

It involves the transfer of amino group from one amino acid to the keto group of a keto acid

The hydroxyl part of the acid is replaced by another NH2

radicle