element

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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 periodicals archive ?
2] shows that the studied chemical elements influence the elongation [A.
We have detected that solely 15 names of the 111 chemical elements are composed by the chemical symbols of others elements of the periodic table.
Carbon, hydrogen and other chemical elements provide the basic building blocks of everything in life.
com/reports/c71989) has announced the addition of The Determination of Chemical Elements in Food : Applications for Atomic and Mass Spectrometry to their offering.
The report specifically named three chemical elements namely cadmium, nickel and arsenic as top pollutants in the Chinese soil.
The sixth formers' workshops are called 'The Magic of Chemistry' and will enable younger children to learn about the chemical elements and their ability to 'magically' change the colour of flames.
In her April 2012 doctoral dissertation at the Technical University of Delft, Sarmento shows how monitoring chemical elements, including metals, in the air and comparing the findings to the incidence of diseases can help identify pollutants that are most harmful to people.
Whereas planets usually form within clouds that include heavier chemical elements, the star HIP 11952 contains very little other than hydrogen and helium.
When using solid pills taken from growing crystals great interest should be paid to the distribution of chemical elements composition because this distribution heavily influences all properties from the semiconductor and ending with the mechanical ones (Ivanov-Omskii, 2009, Singh, 2006).
Not by water and carbon dioxide do plants live - they also need nitrogen and a couple of other chemical elements.
The research will also help us to understand how chemical elements around us are created.

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