1.Structure
Calcium, phosphorus, magnesium and fluoride provide structure to bones and teeth.
Soft tissues gain structural support from phosphorus, potassium, iron and sulphur.
Sulphur is also a fundamental constituent of skin, hair and nails.
2.Maintenance of acid-based balance
This term refers to the maintenance of the body’s concentration of hydrogen ions
(pH). Biological reactions in the cell occur when the pH is right. Anything that
changes the pH of the cell environment may change the way cellular enzymes act.
Inactivation of enzymes results in starvation and death of cells. Acid forming minerals
such as, chlorine, sulphur and phosphorus are found in the extra cellular fluid. They
predominate in foods rich in protein such as meat, fish, poultry, eggs and cereal
products (acid forming foods). Basic or alkaline minerals such as calcium, sodium,
potassium and magnesium tend to predominate in fruits, vegetables and nuts. Milk
contains internal balance of base forming calcium and acid forming phosphorus, and
does not influence acid-base balance
3.Catalysts for biological reactions
Minerals serve as co-factors for many biological reactions. They are not part of initial
compounds or end products but they serve as vital links between enzymes and the
substance which they act on e.g. zinc in known to catalyze about 100 different
reactions. They catalyse many of the separate steps involved in the metabolism of
carbohydrates, fats and proteins. For example, the synthesis of haemoglobin depends
on several mineral elements that are not part of haemoglobin such as iron. Similarly,
although calcium is a catalyst for blood clotting, it is not part of the clot. The
absorption of nutrients from the gastrointestinal tract and the uptake of nutrients by
the cells often depend on minerals (e.g. calcium facilitates the absorption of B12,
sodium and magnesium facilitates absorption of carbohydrates).
4.Components of essential body compounds
Many hormones, enzymes and other vital compounds synthesized in the body contain
minerals as essential parts of their structure. As such, if the required mineral is absent,
the body will be unable to produce adequate amounts of these substances. For example, thyroxin, a hormone which controls energy metabolism requires iodine.
Haemoglobin which transports oxygen to the cells and carbon dioxide from them
contains iron; chlorine is essential for hydrochloric acid production in the stomach.
Mineral containing enzymes are sometimes called metalloenzymes. If the mineral is
unavailable, the enzymes will not be synthesized or will be ineffective. Molybdenum
is part of an enzyme needed to release liver stores of iron. Zinc is part of a protein
splitting enzyme carboxypeptidases secreted into the pancreatic juice.
5.Maintenance of fluid balance
Water comprise of 60% total body weight or 70% of fat free weight. It is present in 3
components, separated by semi-permeable membrane that allows free exchange of
fluids and electrolytes (ions). Intravascular (in blood) compartment includes fluid in
the arteries, veins and capillaries. Intercellular (between cells) bathes individual cells
and provides nourishment, this act as a buffer area. Its volume will adjust to prevent
changes in the volume of the intravascular or extra cellular chambers. Intracellular
fluid is found within the cells. Transcellular compartment includes the fluid which
lubricates the joints and fluid which in the eyeball. This represents a very small
portion and it is not involved in fluid shifts.
The movement of fluid from one compartment to another is controlled by the
concentration of minerals on either side of the membranes. Mineral elements in body
fluids occur as salts that separate into component ions with positive and negative
charges. Charged ions are known as electrolytes and maintain osmotic pressure of
body fluids. As the concentration of electrolytes increase, osmotic pressure increases,
this draws fluid from the compartment with low electrolyte concentration until the
concentration (or pressure) is equalized. Under normal circumstances, the body is able
to prevent a shift in electrolyte concentration between compartments. Shifts however
do occur in abnormal situations.
6.Transmission of nerve impulses
Minerals play a vital role in conducting nerve impulses along a nerve fibre. The
exchange of sodium and potassium across nerve causes the transmission of nerve
impulses. The permeability of membrane changes allowing potassium to leave the
cell. At the same time sodium enters each cell, but is quickly pumped out, this creates
a temporary change in the electrical charge. In this way the message is passed along
the fibre. The transmission of a nerve impulse from one nerve cell to another is also
dependent on neurotransmitter acetylcholine (ACH) at the junction of the two fibres.
The release of ACH is regulated by calcium.
7.Regulation of muscle contraction:
The muscles of the body are bathed in the intercellular fluid. For muscles to function
normally, the composition of this fluid should have a balance between mineral
elements such as calcium which stimulates muscular contraction and sodium,
potassium, and magnesium which exerts relaxing effect. This balance does not depend
on dietary sources and can only be disturbed by hormonal changes.
8.Growth of body tissue
Some minerals such as calcium and phosphorus occur in large concentration in bones
and teeth and are the building material of body tissue. Absence of these will lead to
stunted growth or poorly developed bones and teeth. Other minerals serve as catalysts
to reactions which lead to synthesis of body compounds or to release energy needed
for growth.
Titany answered the question on November 8, 2021 at 05:57