Vitamin and minerals.

What are minerals ?

minerals are ignorganic substances required by the organism in very small amounts for its growth and maintenance of its functional activity.

Function of minerals:Minerals are essential constituent of all cells.Maintenance of osmotic pressureof body fluids.Needed in the formation of bones and teeth and coagulation of blood volume.Play an importent role in water metabolism and regulation of blood volume.Essential in the transport of gases.
Types of minerals:Minerals are divided into two types.Principal elements: These occur in the body in greater concentration ( 60-80%).These include - sodium,potassium,calcium,magnesium,phosphorus,sulpher and chlorine.Trace elements: These occur in the body in lower concentration.These include- arsenic,chromium,cobalt,copper,fluorime,iodine,iron,nickel,silicon,zinc. 

Potassium

Sources : Cereals,bananas orange,chicken,beef,liver,vegetables,water etc
Function :With sodiu,it forms the main base of the body.It is the chief intracellular cation.It is responsible for maintaining the members potential of all irritable cells.It influence the activity of cardiac muscle.Essential in conductionof nerve impulse.

Sodium
Sources : Table salt,mostcereals,milk,fruits vegetables
Signification : It is main base of the body.It is the chief extra cellular cations.It is one of the important cations responsible for
maintaining the internal environment of the body.It maintains the neuro-muscular conductivity and irritability. It maintains cardiac rhythmicity and contractility.It froms the alkali reserve of the body.

Calcium

Sources: Milk (120 mg/100 mI),milk products (800 mg/100 mI),eggs meats, green vegetable, nuts, potato,rice etc

Significance: Calcium help in the formation of bones and teeth. It helps in clotting of blood and curdling of milk.It is essential for
maintaining neuromuscular excitability.It helps to maintain cardiac contractility. Excess calcium will make the heart to stop in systole .It is believe to be actively involved in the membrane transport mechanism. A large amount of calcium is filtered in the kidneys.But 98-99% of the filtered calcium is reabsorption occurs in the proximal tubules and the remainder in the ascending limb of
the loop of henle and the distal tubule.Distal tubular reabsorption is regulated by parathyroid hormone.

Phosphorus

About 80% of the body phosphate is in the bones.Of the rest, the vast majority is organic phosphate and occurs mostly intracellularly. Common examples of such organic phosphates are, nucleotides , ATP,phospholipids,glocose-6-phosphate and so on.
A small amount of phosphate in oue blood is inorganic phosphates are present.A term acid soluble phosphate is used by the clinical
biochemists,most of the acid soluble phosphate.The ulimate source of phosphorous of our body is food.Phosphate excretion occurs
via urine.Phosphorus is absorbed in the duodenum and small intesting by both active transport and passive diffusion.However,unlike
the absorption of Ca2+ the absorption of pi is linearly proportionate to dietary intake.Many stimuli that increase Ca2+ absorption.

Chlorine
Chlorine is the chief anion of the body.About two thirds of the total anoins consists of chloride.The chloride of the HC1 of gastric
juice comes from chloride of the plasma.It contributes to the maintenance of electrolyte and water balance.

Iron
Sources : Raw banana, some green vegetables,wheat,nuts, pulses, egg,meat,liver,kidney, etc.
Iron is absorbed from the small intestine by active absorptive process or pinocytosis in ferrous form.It immediately combines with a beta globulin, apotransferrin,to from transferrin , which is than transported in the blood plasma  and is distributed throughout the body.Excess iron in the blood is deposited in all cells of the body but specially in the liver cells where it combines mainly with a protein, apoferrin, to from ferrin. This iron stored in ferrin is called storage iron.Smaller quentities of the iron in the storage pool are stored in an extremely insoluble from called hemosiderin.         

Zinc
Sources: Meat,liver,eggs, and sea food are good sources.Milk,and whole wheat or dye bread, oatmeal are also good sources
Zink is a compenent of certain enzymes such as carboxy peptidase, carbonic anhydrase,alcohol dehydrogenase etc.Zinc is an integral and essential element of insulin and hence necessary for optimal insulin action.It is also necessary to maintain normal
concentration of vitamin A from the liver .Necessary for tissue repair and wound healing.
           
Iodine
Sources :Water ( mainly sea water ) sea fish,cod liver oil, iodized salt etc.
Iodine is a material essential for thyroid hormone synthesi.Ingested iodine is converted to iodide and absorbed.Iodine is essential for the synthsis thyroid hormones .After absorbtion from the intestine iodides do not remain in blood for a long time because the kidneys have high iodide clearance about 35 m1/min. So 4/5 th of ingested iodide are lost in urine within first three days and remaining 1/5 th is used for thyroid hormone synthesis.

Vitamin

Vitamin means vital amine.Vitamin may be defind as a potent organic compounds which is found in food in variable and minute quantity and must be supplied to the animal organisms from external sourses,so that specific physiological functions,vital to life,may go on normally.The group of substances which are present in food and have antagonistic action to the vitamins. They are collectively
known as antivitamins.    

Causes of vitamin dificiency;Defective intake of vitamins or their precursors in food or as supplements.e.g Malnutrition,Unplanned diet etc.Defect in absorption e.g Diarrhoea,Dysentry,Gastroenteritis,coelic desease,sprue etc.Defect in utilization e.g Wrong way of cooking.Lack of knowledge about health.

Characteristics of vitamin
1.Distribution:The vitamin are widely distributed in nature both in animal and plant kingdoms.
2.Source:All vitamins are manufactured in plants; only a few are manufactured in animals.
3.Daily requirement:Vitamins can perform their work in very low concentration.hence,the total daily requirementis usually very small.
4.Fate:Vitamins are party destroyed digestive process.
5.Some of the vitamine are fat soluble and others are water soluble.

Vitamine A

vitamine A is often used as a collective term for several related biologically active molecules.The term retinods includes both natural and synthetic forms of vitamin A that may or may not show vitamine A activity.A primary alcohol containing a beta-ionone ring with
an unsaturated side chain. Retinol is found in animal tissues as a retiny ester with long-chain fatty acids.The aidehyde derived from
the oxidation of ratinal.Retinoic acid cannot give rise to either retinal or ratino.   

Sources of vitamin A:
1.Animal source:Cod liver oil,halibut liveroil,liver,egg,yolk,milk,butter,cream etc.
2.Vegetable sources:Green leafy vegetables,e.g carrots,papyes,yellow mangoes,yellow bananas,spinach.
Distribution of vitamin A:
Liver,kidney,cream,egg are good sources of perfomed vitamine A .Yellow and dark green vegetables and fruits are good dietary sources of the carotenes,which serve as precursors of vitamine A.Vitamine A is stored in the liver.It may be sufficient to maintain a person without any intake of vitamine A for upto ten month.           
1.In children:Rickets
2.In adult:osteomalacia:(softening of mature bone)

Transport to liver:Retinol ester present in the diet hydrolyzed in the intestinal mucosa, releasing retinol and free fatty acids.Retinol
derived from esters and from the cleavage and reduction of carotenseis reesterified to long chain fatty acids in the intestinal mucosa
and secreted as a component of chylomicrons into the lymphaticsystem. Retinol esters contained in chylomicrons are take up by,
and stored in, the liver.   

Release from liver: When needed,retinol is released from the liver and transported to extrahepatic tissues by the plasma retinol-
binding protein (RBP). The retinol - RBP complex attaches to specific receptorson the surfaceof the cells of peripheral tissues,
permitting retinol to enter. Many tissues contain a cellular retinol-binding protein that carries retinol to sites in the nucleus where the
vitamin acts in a manner analogous to steroid hormones.  

Vitamin E
Sources:Eggs,meats,liver,fish,chicken,milk,soyabine,seed oil especially corn,wheat etc.
Functions:
1.Prevents sterility.
2.Exerts anti-oxidative effect to protect other vitamine in foods.
3.Essential for normal funtion of muscle.
4.Essential for normal foetal development.
5.Necessary for normal repoduction in lower animal.

Vitamin K
Sources:Egg yolk,liver are good sources.It is also synthesized by intestinal flora.Green vegetables as spinach,cabbage,peas,cereals, soyabin.
Function:
1.It helps in the formation prothormbin factor by the liver which takes part in normal coagulation.
2.It shortens the prothrombin, time.
3.It prevents haemorhage.
4.It plays an important rolein oxidative phosphorylation in the mitochondria.
Deficiency sign:Hypo-prothrombinemia with resultant prolonged clotting time.Uncontrolable haemorrhage in new born.Large amount
of vitamin K is synthesized by intestinal flora, so dietary deficiency usually does not occur.An important use of vitamin K is as an
antidote to the anticoagulant drugs such as dicumerol.

Vitamin D
Sources:Exposure to sunlight,cod-liveroil,halibut liver oil,liver,egg,yolk.ergot,yeast etc.
Function:
1.It helps in absorption of calciam and phosphorus from the intestine.It helps in the calcification of new borns.It leads to proper growth of bone and skeleton.
Deficiency effects:In children:Rickets .In adult:osteomalacia:(softening of mature bone)