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Used in it's oxidised form. once inside the palnt phosphate either stays in it's inorganic form or as an ester.(with carbon molecule, or with other phosphates to form pyrophosphate.)

Benefits

Bridging component between two molecules forming a diester. phosphorous also found in the phospholipids of the plasma membrane.Examples of how phosphorous plays a significant structural role in the make up of higher plants.

Phosphorous plays a major functional role in the shape of the esters it forms. an example of one of the esters is ATP, whose phosphate bonds can be broken to release energy for chemical reactions.

The phosphate groups can also be transferred to another substrate or enzyme to activate it. Mediated by enzymes called phosphate kinases, play a significant role in cell signalling.

Inorganic phosphate inhibits starch synthesis in the chloroplasts. In times of deficiency starch begins to build up in the chloroplasts, which then starts to inhibit photosynthesis.

Phosphates can also act as storage molecules in the form of phytates.

Approximatley 0.3%-0.5% of the plants dry weight.

low levels of leaf exspansion

decreased number of leaves and surface area

decrease in photosynthetic efficiency

decrease in shoot to root ratio

suspension of reproductive organs

Poatassium is a highly mobile ion resulting in it being the most prevelant ion in the cytoplasm. Unlike most other nutrients it is not metabolized, however its uptake is linked to the level of cell metabolism.

Benefits

Used to regulate osmotic potential, due to it entering the cell very quickly via ion channels. Also carries out this role in the phloem.

Potasssiums other major role is to regulate the activity of many enzymes by affecting their conformation.

• potassium has an effect,by increasing starch synthase activity.
• potassium ions are also the main counter ion for protons in the chloroplasts and so their concentration can have a major effect on levels of carbon fixation.
• paly a role in stomatal aperture regulation via the opening and closing of K+ channels and the subsequent influx (or not) of water.
• K+ are also involved in responses to external stimuli such as the shutting of plant leaves designed to catch insects.

Requirements

2-5% of plants dried weight

Evidence of deficiency

Growth retardation

Wilting with low water conditions

Decreased frost tolerance

Increased fungal attack

Evidence of excess uptake

inhibits the uptake of other ions

Benefits

Plays a important role in the structure of plant cells. forms molecules in the cell wall with pectin known as calcium pectates. These strengthen the cell wall making the plant resistant to fungal and bacterial attack.

links phosphate and carboxyl groups on phosopholids and protiens which helps to maintain cell wall structure and prevent solute leakage.

Calcium also operates as a second messenger guiding growth of the pollen tube, providing the basis for polar action of auxin, and marking sites of exocytosis.

Involved in the production of callose a fibrin like compound that blocks small plant injuries. calcium also has similar abilities to block flow of nutrients in the pholem which is why it is only present in small quantities.

Invovled in the gravitropic mechanism found in the root caps.

Requirements

0.1 - 0.5% of the plants dry weight

Evidence of deficiency

increased solute efflux,forces increased respiration

increased susceptability to stresses caused by thawing

Benefits

Sulphur is used in the palnt in both structural and functional molecules.

The most prominent set of the structural molecules is the sulpholipids which form quite a large proportion of the membranes of chloroplasts.

Glutathione is an example of a significant functional protien formed using sulphur. it is mainly a housekeeping molecule helping to remove toxic substances such as superoxide and heavy metals from the plant.

Requirement

0.1-0.5%of the plants dry weight.

Evidence of deficiency

High root to shoot ratio, reflecting a lower root hydraulic conductivity, and level of stomatal aperture, and hence reduced photosynthesis.

reduced leaf size.

recline in chloroplast levels, chlorophyll levels drop sharply owing to the high content of sulphur containing protiens in chloroplasts.

Nitrogen fixation in nodules decreases, and the sulphur content of protiens decreases. protien synthesis in general decreases.

Uptake of magnesium into cells is often blocked by being out-competed for binding sites by ions, such as K+, NH4+ and Ca2+ both in the appolplasm and on carrier molecules. luckily it is not required in massive quantities.

Benefits

Plays a vital role in plant biochemistry bringing together many enzymes and their substrates in suitable conformations so that their respective reactions occur at a higher rate.

a similar bridging mechanism is used to hold the two ribosome sub-parts together allowing protien synthesis to take place.

important in the regulation of pH and maintaining an appropriate cation-anion balance.

large quantities of magnesium are also found in chloroplasts where it acts as part of the photosystem, as well as being involved in the enzymes that construct and break down chlorophyll.

Requirement

0.15-0.35% of plants dried weight

Evidence of deficiency

Decreased rates of photosynthesis

Decreased root growth caused by a lower nutrient uptake, possibly due to sub- optmal pH values and reduced tuber growth due to reduced export of starch.

Excess magnesium can be detrimental during periods of drought.

• Effects nutrients have on the development of plants

• Effects nutrients have on yield

• Factors that effect the rate of mineral uptake

• Explanation of the mineral uptake into the cells of plants

• Uptake of mineral nutrients in the apoplasm

• Transport of nutrients throughout the plant

• Nitrogen nutrition