Mineral Nutrition
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PHØSPHØRÜS:
It is absorbed by plants from soil as phosphate ions (H2PO4
- or HPO4
2– ).
It is a constituent of cell membranes, certain proteins, all nucleic acids
and nucleotides.
It is required for all phosphorylation (ATP formation) reactions.
PØTÅSSÏÜM:
Essential in
meristematic tissues,
buds, leaves & root
tips.
It is absorbed as
potassium ion (K+)
It maintains anion-
cation balance in
cells.
It is involved in
protein synthesis,
opening & closing of
stomata, activation
of enzymes and in
the maintenance of
the turgidity of cells.
(NEET 2018)
ÇÅLÇÏÜM:
It is absorbed from the soil as calcium ions (Ca2+).
It is required by meristematic and differentiating tissues and is essential
for the growth of root tip. (NEET-II 2016)
During cell division, it is used in the synthesis of cell wall, particularly as
calcium pectate in middle lamella. It is also needed during the formation
of mitotic spindle.
It accumulates in older leaves.
It is involved in the functioning of the cell membranes. It activates some
enzymes and regulates metabolic activities.