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element

 [el´ĕ-ment]
1. any of the primary parts or constituents of a thing.
2. in chemistry, a simple substance that cannot be decomposed by ordinary chemical means; elements are the basic components of which all matter is composed.

Chemical elements are made up of atoms, each of which consists of a nucleus with a cloud of negatively charged electrons revolving around it. The two major components of the nucleus are protons and neutrons. The number of protons in the atoms of a particular element is always the same, and therefore the physical and chemical properties of the element are always the same. It is possible, however, for a chemical element to exist in several different forms, the difference depending on the number of neutrons in the nucleus of its atoms. Different forms of the same element are called isotopes.

There are at least 105 different chemical elements known. (See Appendix 6 for a list of the elements, and the symbol, atomic weight, and atomic number of each.) The atomic number of an element is determined by the number of protons in the nucleus of one of its atoms. The mass number of an isotope is determined by the total number of neutrons and protons in the nucleus.
Stable Chemical Elements. A stable chemical element is one that contains an optimal ratio or range of ratios between the number of protons and neutrons in the nucleus. A stable element does not spontaneously transmute into another element and therefore does not give off radiation. The stable elements are those that have an atomic number below 84, except for a few, such as potassium and rubidium, which are weakly radioactive.
Radioactive Chemical Elements. A radioactive chemical element does not contain an optimal proton-to-neutron ratio in its atomic nuclei and therefore readily gives off nuclear particles until all nuclei have attained the optimal combination of protons and neutrons. The spontaneous releasing of its nuclear particles changes the radioactive atom into a new atom (transmutation).ƒ

As radioactive elements disintegrate and form new chemical elements, a tremendous amount of energy is released. This emission of energy and nuclear particles is called radiation. The radiations may be electrically charged particles having size and mass, such as alpha particles and beta particles, or they may be nonparticulate and contain no electrical charges, such as gamma rays. Most radioactive elements give off either alpha or beta particles and at the same time emit gamma radiation.
formed e's of the blood the blood cells.
trace element a chemical element present or needed in extremely small amounts by plants and animals; such elements include manganese, copper, cobalt, zinc, and iron.

el·e·ment

(el'ĕ-ment),
1. A substance composed of atoms of only one kind, that is, of identical atomic (proton) number, that therefore cannot be decomposed into two or more elements and that can lose its chemical properties only by union with some other element or by a nuclear reaction changing the proton number.
2. An indivisible structure or entity.
3. A functional entity, frequently exogenous, within a bacterium, such as an extrachromosomal element.
[L. elementum, a rudiment, beginning]

element

/el·e·ment/ (el´ĕ-ment)
1. any of the primary parts or constituents of a thing.
2. in chemistry, a simple substance that cannot be decomposed by chemical means and that is made up of atoms which are alike in their peripheral electronic configurations and so in their chemical properties and also in the number of protons in their nuclei, but which may differ in the number of neutrons in their nuclei and so in their mass number and in their radioactive properties.
3. in the philosophies underlying some complementary medicine systems, a member of a group of basic substances that give rise to everything that exists.

five elements 
1. see under phase.
2. in ayurvedic tradition, the basic entities (earth, air, fire, water, and space) whose interaction gives rise to material existence.
formed elements of the blood  the blood cells.
trace elements  chemical elements distributed throughout the tissues in very small amounts and that are either essential in nutrition, as cobalt, copper, etc., or harmful, as selenium.
transposable element  see transposon.

element

Etymology: L, elementum, first principle
one of more than 100 primary, simple substances that cannot be broken down by chemical means into any other substance. Each atom of any element contains a specific number of protons in the nucleus and an equal number of electrons outside the nucleus. In most elements, the nucleus may contain a variable number (high or low) of neutrons. An element with a disproportionate number of neutrons may be unstable, in which case the nucleus undergoes radioactive decay into a more stable element. See also atom, compound, molecule, radioactivity.

element

EBM
In the context of a trial design, a basic unit of time within a clinical trial, which describes what is expected to happen to the subject (patient) during the period, when the period begins and rules for ending the element.

Informatics
A section of text in an XML document delineated by start and end tags, or, in the case of empty elements (elements with no content, only attributes), indicated by an empty tag.

el·e·ment

(el'ĕ-mĕnt)
1. A substance composed of atoms of only one kind, i.e., of identical atomic (proton) number, which therefore cannot be decomposed into two or more elements, and which can lose its chemical properties only by union with some other element or by a nuclear reaction changing the proton number.
2. An indivisible structure or entity.
3. A functional entity, frequently exogenous, within a bacterium, such as an extrachromosomal element.
[L. elementum, a rudiment, beginning]

element

(el'e-ment) [L. elementum, a rudiment]
Enlarge picture
TABLE OF ELEMENTS IN THE BODY
In chemistry, a pure substance consisting of only one type of atom. Further breakdown by nonchemical means of an element results in subatomic particles (protons, neutrons and electrons), which are indistinguishable from those from other elements. Elements exist in free and combined states. There are 110 named elements and others yet to be fully characterized and named. See: illustration

Oxygen, carbon, hydrogen, nitrogen, phosphorus, and sulfur are found in all living organisms. These six elements and calcium make up 99% of the human body mass. Sodium, potassium, magnesium, chlorine, iodine, and iron form 0.9% of the body mass.

mobile element

A nucleotide sequence that can be inserted successfully into several different places in the genome.

movable genetic element

Transposon.

rare earth element

One of a series of metallic elements that follow lanthanum (at. no. 57) in the periodic table of elements and that have oxides with similar properties. The series comprises the 14-element lanthanide series (at. nos. 58-71 and includes praseodymium, promethium, and ytterbium.

trace element

An element needed by the body in very small amounts; many are essential for enzyme functioning. Trace elements include chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, and zinc.

ultratrace element

Any of those elements for which laboratory animals seem to have tiny dietary requirements, typically less than 1 µg/g. Elements in this category include arsenic, boron, bromine, cadmium, chromium, fluorine, lead, lithium, molybdenum, nickel, silicon, tin, and vanadium.

element

a pure substance consisting of only one type of atom, that cannot be destroyed by normally available heat or electrical energy.

element

substance composed entirely of identical atoms; it will only lose its unique chemical property by bonding with another element or substance

element,

n any substance that cannot be reduced into a less complex substance, all atoms of which are defined as having the same number of protons.

el·e·ment

(el'ĕ-mĕnt)
Substance composed of atoms of only one kind that therefore cannot be decomposed into two or more elements and can lose its chemical properties only by union with another element or by nuclear reaction changing the proton number.
[L. elementum, a rudiment, beginning]

element,

n a simple substance that cannot be decomposed by chemical means and is made up of atoms that are alike in their peripheral electronic configuration and chemical properties but differ in their nuclei, atomic weights, and radioactive properties.

element

1. any of the primary parts or constituents of a thing.
2. in chemistry, a simple substance that cannot be decomposed by ordinary chemical means; the basic 'stuff' of which all matter is composed.
Chemical elements are made up of atoms. Each atom consists of a nucleus with a cloud of negatively charged particles (electrons) revolving around it. The two major components of the nucleus are protons and neutrons. The number of protons in the atoms of a particular element is always the same, and therefore the physical and chemical properties of the element are always the same. It is possible, however, for a chemical element to exist in several different forms, the difference depending on the number of neutrons in the nucleus of its atoms. Different forms of the same element are called isotopes.
There are at least 105 different chemical elements known. Table 6 lists the elements, and the symbol, atomic weight and atomic number of each. The atomic number of an element is determined by the number of protons in the nucleus of an atom of the element. The mass number of an isotope is determined by the total number of neutrons and protons in the nucleus.

formed e's (of the blood)
erythrocytes, leukocytes and platelets.
element points
trace element
a chemical element present or needed in extremely small amount by plants and animals, such as manganese, copper, cobalt, zinc, iron. See also trace element.

Patient discussion about element

Q. what consider to be a good nutrition for children? does it has to include some specific nutrition elements?

A. there's many things you should consider about children's nutrition, the amount of books written about kids nutrition can fill a library...
vitamins, organic vs industrial, fast food vs home made etc.
here are 2 video libraries that i'm sure you'll find all the info you seek in them-

http://www.thedoctorsvideos.com/categories/26/Nutrition

http://www.drmdk.com/html/nutrition.html

More discussions about element
References in classic literature ?
Thus they thir doubtful consultations dark Ended rejoycing in thir matchless Chief: As when from mountain tops the dusky clouds Ascending, while the North wind sleeps, o'respread Heav'ns chearful face, the lowring Element Scowls ore the dark'nd lantskip Snow, or showre; If chance the radiant Sun with farewell sweet Extend his ev'ning beam, the fields revive, The birds thir notes renew, and bleating herds Attest thir joy, that hill and valley rings.
Of course there were those who were opposed to any such recognition of the rights of the Negro, but the Board of Directors, composed of men who represented the best and most progressive element in the South, had their way, and voted to invite a black man to speak on the opening day.
absolute continuity) and thereby corrects the inevitable error which the human mind cannot avoid when it deals with separate elements of motion instead of examining continuous motion.
In regard to the sterility of hybrids, in which the sexual elements are imperfectly developed, the case is very different.
Idealism, the tendency opposite to Realism, seeks to emphasize the spiritual and other higher elements, often to bring out the spiritual values which lie beneath the surface.
These ways, taken together, are called the "cognitive" elements in mind, and it is these that will occupy us most during the following lectures.
Vronsky at the first moment felt embarrassed at not even knowing of the first part of the Two Elements, of which the author spoke as something well known.
But when you are invited to hunt the shark in its natural element, you would perhaps reflect before accepting the invitation.
At such moments, the roaring of the flames, the crackling of the furious element, with the tearing of falling branches, and occasionally the thundering echoes of some falling tree, united to alarm the victims.
I suspected that Blanche Stroeve's violent dislike of Strickland had in it from the beginning a vague element of sexual attraction.
As for Polychrome--the Rainbow's Daughter--and stupid little Button-Bright, they seem to have brought a new element of fun into these Oz stories, and I am glad I discovered them.
Contentment with our lot is an element of happiness.

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