Which describes the role of vitamins?

Answer & explanation:

Vitamins are substances that the body is unable to produce and therefore need to be part of the diet, since a low amount of these vitamins may lead to some diseases (hypovitaminosis).

Its main sources are fruits and vegetables, but they can also be found in meat, milk, eggs and cereals.

Vitamins play several roles in development and organic metabolism. However, they are neither used as energy nor as cellular replacement material. They work as additives, so they are indispensable to the energy production mechanism and others, but in small quantities.

They may be classified as water-soluble and fat-soluble.

Fat-soluble vitamins include vitamins A, D, E and K. Bile is required for the absorption of fat-soluble vitamins, because the body stores fat-soluble vitamins and an excess intake (hypervitaminosis) can result in symptoms of toxicity.

Water-soluble vitamins include vitamins B and C, which do not depend on bile for absorption, most of which is not stored in the body. Excess water-soluble vitamins are usually excreted in the urine. Excretion, however, does not preclude the possibility of toxicity in response to a mega dosing of water-soluble vitamins.

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.